Semiconducting polymers

ABSTRACT

The invention relates to novel polymers containing repeating units based on benzodifuran, benzodipyrrole or benzodithiophene, monomers and methods for their preparation, their use as semiconductors in organic electronic (OE) devices, especially in organic photovoltaic (OPV) devices, and to OE and OPV devices comprising these polymers.

FIELD OF THE INVENTION

The invention relates to novel polymers containing repeating units basedon benzodifuran, benzodipyrrole or benzodithiophene, monomers andmethods for their preparation, their use as semiconductors in organicelectronic (OE) devices, especially in organic photovoltaic (OPV)devices, and to OE and OPV devices comprising these polymers.

BACKGROUND OF THE INVENTION

In recent years there has been growing interest in the use ofsemiconducting polymers for electronic applications. One particular areaof importance is organic photovoltaics (OPV). Polymers have found use inOPVs as they allow devices to be manufactured by solution-processingtechniques such as spin casting, dip coating or ink jet printing.Solution processing can be carried out cheaper and on a larger scalecompared to the evaporative techniques used to make inorganic thin filmdevices. Currently, polymer based photovoltaic devices are achievingefficiencies up to 7%.

There is still a need for organic semiconducting (OSC) materials thatare easy to synthesize, especially by methods suitable for massproduction, show good structural organization and film-formingproperties, exhibit good electronic properties, especially a high chargecarrier mobility, good processability, especially a high solubility inorganic solvents, and high stability in air. Especially for use in OPVcells, there is a need for OSC materials having a low bandgap, whichenable improved light harvesting by the photoactive layer and can leadto higher cell efficiencies.

It was an aim of the present invention to provide compounds for use asorganic semiconducting materials that do not have the drawbacks of priorart materials as described above, are easy to synthesize, especially bymethods suitable for mass production, and do especially show goodprocessability, high stability, good solubility in organic solvents,high charge carrier mobility, and a low bandgap. Another aim of theinvention was to extend the pool of OSC materials available to theexpert. Other aims of the present invention are immediately evident tothe expert from the following detailed description.

The inventors of the present invention have found that these aims can beachieved by providing conjugated semiconducting polymers based on a3,7-diaryl-benzo[1,2-b;4,5-b′]difuran-2,6-dione or3,7-diaryl-benzo[1,2-b;4,5-b′]dipyrrole-2,6-dione core:

wherein X is O, S or N—R, R is e.g. H or alkyl, and Ar¹ and Ar² arearyl.

The monomers and polymers of the present invention are especiallysuitable for large scale production. At the same time, they show goodprocessability, high solubility in organic solvents, low bandgap, highcharge carrier mobility and high oxidative stability, and are promisingmaterials for organic electronic OE devices, especially for OPV devices.

Derivatives of the benzodifuranone and benzodipyrrolidone have been usedas red and purple dyes or pigments in U.S. Pat. No. 4,115,404 andGreenhalgh, C. W.; Carey, J. L.; Newton, D. F. Dyes and Pigments, 1980,1, 103-120. Derivatives of the benzodithiophenone are described inNakatsuka, M. et al., Chemistry Letters, 1983, 905-908. However, it hashitherto not been suggested to use such compounds as recurring units insemiconducting polymers.

SUMMARY OF THE INVENTION

The invention relates to a conjugated polymer comprising one or moreidentical or different repeating units of formula I:

wherein the asterisks indicate a link to neighbored groups, and

-   X is O, S or NR^(x),-   R is, on each occurrence identically or differently, H, F, Cl, Br,    I, CN, or straight-chain, branched or cyclic alkyl with 1 to 35 C    atoms, in which one or more non-adjacent C atoms are optionally    replaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —CR⁰═CR⁰⁰— or    —C≡C— and in which one or more H atoms are optionally replaced by F,    Cl, Br, I or CN, or denote aryl, heteroaryl, aryloxy, heteroaryloxy,    arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy,    heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl    having 4 to 30 ring atoms that is unsubstituted or substituted by    one or more non-aromatic groups R¹,-   R^(x) is on each occurrence identically or differently    straight-chain, branched or cyclic alkyl with 1 to 30 C atoms, in    which one or more non-adjacent C atoms are optionally replaced by    —O—, —S—, —CO—, —CO—O—, —O—CO—, O—CO—O—, —CR⁰═CR⁰⁰— or —C≡C— and in    which one or more H atoms are optionally replaced by F, Cl, Br, I or    CN,-   R⁰ and R⁰⁰ are independently of each other H or optionally    substituted carbyl or hydrocarbyl optionally comprising one or more    hetero atoms,-   R¹ is on each occurrence identically or differently H, halogen, —CN,    —NC, —NCO, —NCS, —OCN, —SCN, —C(═O)NR⁰R⁰⁰, —C(═O)X⁰, —C(═O)R⁰, —NH₂,    —NR⁰R⁰⁰, —SH, —SR⁰, —SO₃H, —SO₂R⁰, —OH, —NO₂, —CF₃, —SF₅, optionally    substituted silyl, carbyl or hydrocarbyl with 1 to 40 C atoms that    is optionally substituted and optionally comprises one or more    hetero atoms, or P-Sp-,-   P is a polymerisable or crosslinkable group,-   Sp is a spacer group or a single bond,-   X⁰ is halogen.

The invention further relates to a conjugated polymer comprising one ormore repeating units which contain a unit of formula I and/or containone or more units (hereinafter also referred to as Ar¹, Ar² and Ar³)selected from aryl and heteroaryl units that are optionally substituted,and wherein at least one of the repeating units in the polymer containsat least one unit of formula I.

Preferably these polymers are selected of formula II:—[(Ar¹—U—Ar²)_(x)—(Ar³)_(y)]_(n)—  IIwherein

-   U is on each occurrence identically or differently a unit of formula    I as described above and below,-   Ar¹, Ar², Ar³ are, on each occurrence identically or differently,    and independently of each other, optionally substituted aryl or    heteroaryl,-   Y¹ and Y² are independently of each other H, F, Cl or CN,-   x is on each occurrence identically or differently 0, 1 or 2,    wherein in at least one repeating unit, i.e. in at least one unit    —[(Ar¹—U—Ar²)_(x)—(Ar³)_(y)]—, x is 1,-   y is on each occurrence identically or differently 0, 1 or 2,-   n is an integer>1.

The invention further relates to monomers containing a unit of formulaI, which are suitable for the preparation of polymers as described aboveand below.

The invention further relates to a mixture or blend comprising one ormore polymers according to the present invention and one or moreadditional compounds or polymers which are preferably selected fromcompounds and polymers having semiconducting, charge transport,hole/electron transport, hole/electron blocking, electricallyconducting, photoconducting or light emitting properties.

The invention further relates to a formulation comprising one or morepolymers, mixtures or blends according to the present invention andoptionally one or more solvents, preferably selected from organicsolvents.

The invention further relates to the use of polymers, mixtures, blendsand formulations according to the present invention as charge transport,semiconducting, electrically conducting, photoconducting or lightemitting material in optical, electrooptical, electronic,electroluminescent or photoluminescent components or devices.

The invention further relates to a charge transport, semiconducting,electrically conducting, photoconducting or light emitting material orcomponent comprising one or more polymers, polymer blends offormulations according to the present invention.

The invention further relates to an optical, electrooptical orelectronic component or device comprising one or more polymers, polymerblends, formulations, components or materials according to the presentinvention.

The optical, electrooptical, electronic electroluminescent andphotoluminescent components or devices include, without limitation,organic field effect transistors (OFET), thin film transistors (TFT),integrated circuits (IC), logic circuits, capacitors, radio frequencyidentification (RFID) tags, devices or components, organic lightemitting diodes (OLED), organic light emitting transistors (OLET), flatpanel displays, backlights of displays, organic photovoltaic devices(OPV), solar cells, laser diodes, photoconductors, photodetectors,electrophotographic devices, electrophotographic recording devices,organic memory devices, sensor devices, charge injection layers, chargetransport layers or interlayers in polymer light emitting diodes(PLEDs), organic plasmon-emitting diodes (OPEDs), Schottky diodes,planarising layers, antistatic films, polymer electrolyte membranes(PEM), conducting substrates, conducting patterns, electrode materialsin batteries, alignment layers, biosensors, biochips, security markings,security devices, and components or devices for detecting anddiscriminating DNA sequences.

DETAILED DESCRIPTION OF THE INVENTION

The monomers and polymers of the present invention are easy tosynthesize and exhibit several advantageous properties, like a lowbandgap, a high charge carrier mobility, a high solubility in organicsolvents, a good processability for the device manufacture process, ahigh oxidative stability and a long lifetime in electronic devices.

In addition, they show the following advantageous properties:

i) The repeating units of formula I contain two five-membered rings thatare fused to the central benzene ring which itself is contained withinthe backbone of the polymer. The pre-established quinoidal bandstructure of the cores increases the quinoidal band structure of theresultant polymers, and therefore lowers the band gap of the polymer,thus improving the light harvesting ability of the material.ii) Additional solubility can be introduced into the polymer byinclusion of solubilising groups at the R positions or co-monomerscontaining multiple solubilising groups. The substituents in 2- and6-position do thus increase the solubility of the polymer in commonorganic solvents, allowing the material to be easily solution processed.iii) The units of formula I are planar structures that enable strongpi-pi stacking in the solid state leading to improved charge transportproperties in the form of higher charge carrier mobility.iv) The addition of reactive functionalities on the 3- and 7-positionsof the -benzo[1,2-b;4,5-b′]difuran-2,6-dione,benzo[1,2-b;4,5-b′]dithiophene-2,6-dione orbenzo[1,2-b;4,5-b′]dipyrrole-2,6-dione units enables the preparation ofregioregular chemically polymerized homopolymers and copolymers. Suchpolymers can be obtained for example using Yamamoto, Suzuki or Stillecoupling polymerization methods, which are known from the literature. Bythese preparative methods, the regioregular polymer has higherstructural order in the solid state compared to regioirregular materialssynthesized using a non-selective polymerization method. This leads to apolymer with a higher degree of intermolecular order and thereforehigher charge carrier mobility for application in OFET and OPV devices.v) Additional fine-tuning of the electronic energies (HOMO/LUMO levels)by either careful selection of Ar units on each side ofbenzo[1,2-b;4,5-b′]difuran-2,6-dione,benzo[1,2-b;4,5-b′]dithiophene-2,6-dione orbenzo[1,2-b;4,5-b′]dipyrrole-2,6-dione core or co-polymerisation withappropriate co-monomer(s) can afford highly promising candidatematerials for OPV applications.

The term “polymer” generally means a molecule of high relative molecularmass, the structure of which essentially comprises the multiplerepetition of units derived, actually or conceptually, from molecules oflow relative molecular mass (PAC, 1996, 68, 2291). The term “oligomer”generally means a molecule of intermediate relative molecular mass, thestructure of which essentially comprises a small plurality of unitsderived, actually or conceptually, from molecules of lower relativemolecular mass (PAC, 1996, 68, 2291). In a preferred sense according tothe present invention a polymer means a compound having >1, preferably 5repeating units, and an oligomer means a compound with >1 and <10,preferably <5, repeating units.

Above and below, in a formula showing a polymer or a repeating unit,like formula I and its subformulae, an asterisk (“*”) denotes a linkageto the adjacent repeating unit in the polymer chain.

The terms “repeating unit” and “monomeric unit” mean the constitutionalrepeating unit (CRU), which is the smallest constitutional unit therepetition of which constitutes a regular macromolecule, a regularoligomer molecule, a regular block or a regular chain (PAC, 1996, 68,2291).

The term “leaving group” means an atom or group (charged or uncharged)that becomes detached from an atom in what is considered to be theresidual or main part of the molecule taking part in a specifiedreaction (see also PAC, 1994, 66, 1134).

The term “conjugated” means a compound containing mainly C atoms withsp²-hybridisation (or optionally also sp-hybridisation), which may alsobe replaced by hetero atoms. In the simplest case this is for example acompound with alternating C—C single and double (or triple) bonds, butdoes also include compounds with units like 1,3-phenylene. “Mainly”means in this connection that a compound with naturally (spontaneously)occurring defects, which may lead to interruption of the conjugation, isstill regarded as a conjugated compound.

Unless stated otherwise, the molecular weight is given as the numberaverage molecular weight M_(n) or weight average molecular weight M_(w),which is determined by gel permeation chromatography (GPC) againstpolystyrene standards in eluent solvents such as tetrahydrofuran,trichloromethane (TCM, chloroform), chlorobenzene or1,2,4-trichlorobenzene. Unless stated otherwise, trichloromethane isused as solvent. The degree of polymerization (n) means the numberaverage degree of polymerization given as n=M_(n)/M_(U) wherein M_(U) isthe molecular weight of the single repeating unit as described in J. M.G. Cowie, Polymers: Chemistry & Physics of Modern Materials, Blackie,Glasgow, 1991.

The term “carbyl group” as used above and below denotes any monovalentor multivalent organic radical moiety which comprises at least onecarbon atom either without any non-carbon atoms (like for example—C≡C—), or optionally combined with at least one non-carbon atom such asN, O, S, P, Si, Se, As, Te or Ge (for example carbonyl etc.). The term“hydrocarbyl group” denotes a carbyl group that does additionallycontain one or more H atoms and optionally contains one or more heteroatoms like for example N, O, S, P, Si, Se, As, Te or Ge.

A carbyl or hydrocarbyl group comprising a chain of 3 or more C atomsmay also be straight-chain, branched and/or cyclic, including spiroand/or fused rings.

Preferred carbyl and hydrocarbyl groups include alkyl, alkoxy,alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy and alkoxycarbonyloxy,each of which is optionally substituted and has 1 to 40, preferably 1 to25, very preferably 1 to 18 C atoms, furthermore optionally substitutedaryl or aryloxy having 6 to 40, preferably 6 to 25 C atoms, furthermorealkylaryloxy, arylcarbonyl, aryloxycarbonyl, arylcarbonyloxy andaryloxycarbonyloxy, each of which is optionally substituted and has 6 to40, preferably 7 to 40 C atoms, wherein all these groups do optionallycontain one or more hetero atoms, preferably selected from N, O, S, P,Si, Se, As, Te and Ge.

The carbyl or hydrocarbyl group may be a saturated or unsaturatedacyclic group, or a saturated or unsaturated cyclic group. Unsaturatedacyclic or cyclic groups are preferred, especially aryl, alkenyl andalkynyl groups (especially ethynyl). Where the C₁-C₄₀ carbyl orhydrocarbyl group is acyclic, the group may be straight-chain orbranched. The C₁-C₄₀ carbyl or hydrocarbyl group includes for example: aC₁-C₄₀ alkyl group, a C₁-C₄₀ alkoxy or oxaalkyl group, a C₂-C₄₀ alkenylgroup, a C₂-C₄₀ alkynyl group, a C₃-C₄₀ allyl group, a C₄-C₄₀alkyldienyl group, a C₄-C₄₀ polyenyl group, a C₆-C₁₈ aryl group, aC₆-C₄₀ alkylaryl group, a C₆-C₄₀ arylalkyl group, a C₄-C₄₀ cycloalkylgroup, a C₄-C₄₀ cycloalkenyl group, and the like. Preferred among theforegoing groups are a C₁-C₂₀ alkyl group, a C₂-C₂₀ alkenyl group, aC₂-C₂₀ alkynyl group, a C₃-C₂₀ allyl group, a C₄-C₂₀ alkyldienyl group,a C₆-C₁₂ aryl group, and a C₄-C₂₀ polyenyl group, respectively. Alsoincluded are combinations of groups having carbon atoms and groupshaving hetero atoms, like e.g. an alkynyl group, preferably ethynyl,that is substituted with a silyl group, preferably a trialkylsilylgroup.

Aryl and heteroaryl preferably denote a mono-, bi- or tricyclic aromaticor heteroaromatic group with 4 to 30 ring C atoms that may also comprisecondensed rings and is optionally substituted with one or more groups Las defined above.

Very preferred substituents L are selected from halogen, most preferablyF, or alkyl, alkoxy, oxaalkyl, thioalkyl, fluoroalkyl and fluoroalkoxywith 1 to 12 C atoms or alkenyl, alkynyl with 2 to 12 C atoms.

Especially preferred aryl and heteroaryl groups are phenyl in which, inaddition, one or more CH groups may be replaced by N, naphthalene,thiophene, selenophene, thienothiophene, dithienothiophene, fluorene andoxazole, all of which can be unsubstituted, mono- or polysubstitutedwith L as defined above. Very preferred rings are selected from pyrrole,preferably N-pyrrole, pyridine, preferably 2- or 3-pyridine, pyrimidine,thiophene preferably 2-thiophene, selenophene, preferably 2-selenophene,thieno[3,2-b]thiophene, thiazole, thiadiazole, oxazole and oxadiazole,especially preferably thiophene-2-yl, 5-substituted thiophene-2-yl orpyridine-3-yl, all of which can be unsubstituted, mono- orpolysubstituted with L as defined above.

An alkyl or alkoxy radical, i.e. where the terminal CH₂ group isreplaced by —O—, can be straight-chain or branched. It is preferablystraight-chain, has 2, 3, 4, 5, 6, 7 or 8 carbon atoms and accordinglyis preferably ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl,ethoxy, propoxy, butoxy, pentoxy, hexoxy, heptoxy, or octoxy,furthermore methyl, nonyl, decyl, undecyl, dodecyl, tridecyl,tetradecyl, pentadecyl, nonoxy, decoxy, undecoxy, dodecoxy, tridecoxy ortetradecoxy, for example.

An alkenyl group, wherein one or more CH₂ groups are replaced by —CH═CH—can be straight-chain or branched. It is preferably straight-chain, has2 to 10 C atoms and accordingly is preferably vinyl, prop-1-, orprop-2-enyl, but-1-, 2- or but-3-enyl, pent-1-, 2-, 3- or pent-4-enyl,hex-1-, 2-, 3-, 4- or hex-5-enyl, hept-1-, 2-, 3-, 4-, 5- orhept-6-enyl, oct-1-, 2-, 3-, 4-, 5-, 6- or oct-7-enyl, non-1-, 2-, 3-,4-, 5-, 6-, 7- or non-8-enyl, dec-1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- ordec-9-enyl.

Especially preferred alkenyl groups are C₂-C₇-1E-alkenyl,C₄-C₇-3E-alkenyl, C₅-C₇-4-alkenyl, C₆-C₇-5-alkenyl and C₇-6-alkenyl, inparticular C₂-C₇-1E-alkenyl, C₄-C₇-3E-alkenyl and C₅-C₇-4-alkenyl.Examples for particularly preferred alkenyl groups are vinyl,1E-propenyl, 1E-butenyl, 1E-pentenyl, 1E-hexenyl, 1E-heptenyl,3-butenyl, 3E-pentenyl, 3E-hexenyl, 3E-heptenyl, 4-pentenyl, 4Z-hexenyl,4E-hexenyl, 4Z-heptenyl, 5-hexenyl, 6-heptenyl and the like. Groupshaving up to 5 C atoms are generally preferred.

An oxaalkyl group, i.e. where one CH₂ group is replaced by —O—, ispreferably straight-chain 2-oxapropyl (=methoxymethyl),2-(=ethoxymethyl) or 3-oxabutyl (=2-methoxyethyl), 2-, 3-, or4-oxapentyl, 2-, 3-, 4-, or 5-oxahexyl, 2-, 3-, 4-, 5-, or 6-oxaheptyl,2-, 3-, 4-, 5-, 6- or 7-oxaoctyl, 2-, 3-, 4-, 5-, 6-, 7- or 8-oxanonylor 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-oxadecyl, for example. Oxaalkyl, i.e.where one CH₂ group is replaced by —O—, is preferably straight-chain2-oxapropyl (=methoxymethyl), 2-(=ethoxymethyl) or 3-oxabutyl(=2-methoxyethyl), 2-, 3-, or 4-oxapentyl, 2-, 3-, 4-, or 5-oxahexyl,2-, 3-, 4-, 5-, or 6-oxaheptyl, 2-, 3-, 4-, 5-, 6- or 7-oxaoctyl, 2-,3-, 4-, 5-, 6-, 7- or 8-oxanonyl or 2-, 3-, 4-, 5-, 6-, 7-, 8- or9-oxadecyl, for example.

In an alkyl group wherein one CH₂ group is replaced by —O— and one by—CO—, these radicals are preferably neighbored. Accordingly theseradicals together form a carbonyloxy group —CO—O— or an oxycarbonylgroup —O—CO—. Preferably this group is straight-chain and has 2 to 6 Catoms. It is accordingly preferably acetyloxy, propionyloxy, butyryloxy,pentanoyloxy, hexanoyloxy, acetyloxymethyl, propionyloxymethyl,butyryloxymethyl, pentanoyloxymethyl, 2-acetyloxyethyl,2-propionyloxyethyl, 2-butyryloxyethyl, 3-acetyloxypropyl,3-propionyloxypropyl, 4-acetyloxybutyl, methoxycarbonyl, ethoxycarbonyl,propoxycarbonyl, butoxycarbonyl, pentoxycarbonyl, methoxycarbonylmethyl,ethoxy-carbonylmethyl, propoxycarbonylmethyl, butoxycarbonylmethyl,2-(methoxycarbonyl)ethyl, 2-(ethoxycarbonyl)ethyl,2-(propoxy-carbonyl)ethyl, 3-(methoxycarbonyl)propyl,3-(ethoxycarbonyl)propyl, 4-(methoxycarbonyl)-butyl.

An alkyl group wherein two or more CH₂ groups are replaced by —O— and/or—COO— can be straight-chain or branched. It is preferably straight-chainand has 3 to 12 C atoms. Accordingly it is preferablybis-carboxy-methyl, 2,2-bis-carboxy-ethyl, 3,3-bis-carboxy-propyl,4,4-bis-carboxy-butyl, 5,5-bis-carboxy-pentyl, 6,6-bis-carboxy-hexyl,7,7-bis-carboxy-heptyl, 8,8-bis-carboxy-octyl, 9,9-bis-carboxy-nonyl,10,10-bis-carboxy-decyl, bis-(methoxycarbonyl)-methyl,2,2-bis-(methoxycarbonyl)-ethyl, 3,3-bis-(methoxycarbonyl)-propyl,4,4-bis-(methoxycarbonyl)-butyl, 5,5-bis-(methoxycarbonyl)-pentyl,6,6-bis-(methoxycarbonyl)-hexyl, 7,7-bis-(methoxycarbonyl)-heptyl,8,8-bis-(methoxycarbonyl)-octyl, bis-(ethoxycarbonyl)-methyl,2,2-bis-(ethoxycarbonyl)-ethyl, 3,3-bis-(ethoxycarbonyl)-propyl,4,4-bis-(ethoxycarbonyl)-butyl, 5,5-bis-(ethoxycarbonyl)-hexyl.

A thioalkyl group, i.e where one CH₂ group is replaced by —S—, ispreferably straight-chain thiomethyl (—SCH₃), 1-thioethyl (—SCH₂CH₃),1-thiopropyl (=—SCH₂CH₂CH₃), 1-(thiobutyl), 1-(thiopentyl),1-(thiohexyl), 1-(thioheptyl), 1-(thiooctyl), 1-(thiononyl),1-(thiodecyl), 1-(thioundecyl) or 1-(thiododecyl), wherein preferablythe CH₂ group adjacent to the sp² hybridised vinyl carbon atom isreplaced.

A fluoroalkyl group is preferably straight-chain perfluoroalkylC_(i)F_(2i+1), wherein i is an integer from 1 to 15, in particular CF₃,C₂F₅, C₃F₇, C₄F₉.

The above-mentioned alkyl, alkoxy, alkenyl, oxaalkyl, thioalkyl,carbonyl and carbonyloxy groups can be achiral or chiral groups.Particularly preferred chiral groups are 2-butyl (=1-methylpropyl),2-methylbutyl, 2-methylpentyl, 3-methylpentyl, 2-ethylhexyl,2-propylpentyl, in particular 2-methylbutyl, 2-methylbutoxy,2-methylpentoxy, 3-methylpentoxy, 2-ethyl-hexoxy, 1-methylhexoxy,2-octyloxy, 2-oxa-3-methylbutyl, 3-oxa-4-methylpentyl, 4-methylhexyl,2-hexyl, 2-octyl, 2-nonyl, 2-decyl, 2-dodecyl, 6-meth-oxyoctoxy,6-methyloctoxy, 6-methyloctanoyloxy, 5-methylheptyloxy-carbonyl,2-methylbutyryloxy, 3-methylvaleroyloxy, 4-methylhexanoyloxy,2-chloropropionyloxy, 2-chloro-3-methylbutyryloxy,2-chloro-4-methyl-valeryl-oxy, 2-chloro-3-methylvaleryloxy,2-methyl-3-oxapentyl, 2-methyl-3-oxahexyl, 1-methoxypropyl-2-oxy,1-ethoxypropyl-2-oxy, 1-propoxypropyl-2-oxy, 1-butoxypropyl-2-oxy,2-fluorooctyloxy, 2-fluorodecyloxy, 1,1,1-trifluoro-2-octyloxy,1,1,1-trifluoro-2-octyl, 2-fluoromethyloctyloxy for example. Verypreferred are 2-hexyl, 2-octyl, 2-octyloxy, 1,1,1-trifluoro-2-hexyl,1,1,1-trifluoro-2-octyl and 1,1,1-trifluoro-2-octyloxy.

Preferred achiral branched groups are isopropyl, isobutyl(=methylpropyl), isopentyl (=3-methylbutyl), tert. butyl, isopropoxy,2-methyl-propoxy and 3-methylbutoxy.

In another preferred embodiment of the present invention, R is selectedfrom primary, secondary or tertiary alkyl or alkoxy with 1 to 30 Catoms, wherein one or more H atoms are optionally replaced by F, oraryl, aryloxy, heteroaryl or heteroaryloxy that is optionally alkylatedor alkoxylated and has 4 to 30 ring atoms. Very preferred groups of thistype are selected from the group consisting of the following formulae

wherein “ALK” denotes optionally fluorinated, preferably linear, alkylor alkoxy with 1 to 20, preferably 1 to 12 C-atoms, in case of tertiarygroups very preferably 1 to 9 C atoms, and the dashed line denotes thelink to the ring to which these groups are attached. Especiallypreferred among these groups are those wherein all ALK subgroups areidentical.

—CY¹═CY²— is preferably —CH═CH—, —CF═CF— or —CH═C(CN)—.

Halogen is F, Cl, Br or I, preferably F, Cl or Br.

The polymers may also be substituted with a polymerisable orcrosslinkable reactive group, which is optionally protected during theprocess of forming the polymer. Particular preferred polymers of thistype are those of formula I wherein R¹ denotes P-Sp. These polymers areparticularly useful as semiconductors or charge transport materials, asthey can be crosslinked via the groups P, for example by polymerisationin situ, during or after processing the polymer into a thin film for asemiconductor component, to yield crosslinked polymer films with highcharge carrier mobility and high thermal, mechanical and chemicalstability.

Preferably the polymerisable or crosslinkable group P is selected fromCH₂═CW¹—CO—O—, CH₂═CW¹—CO—,

CH₂═CW²—(O)_(k1)—, CW¹═CH—CO—(O)_(k3)—, CW¹═CH—CO—NH—, CH₂═CW¹—CO—NH—,CH₃—CH═CH—O—, (CH₂═CH)₂CH—OCO—, (CH₂═CH—CH₂)₂CH—O—CO—, (CH₂═CH)₂CH—O—,(CH₂═CH—CH₂)₂N—, (CH₂═CH—CH₂)₂N—CO—, HO—CW²W³—, HS—CW²W³—, HW²N—,HO—CW²W³—NH—, CH₂═CH—(CO—O)_(k1)-Phe-(O)_(k2)—,CH₂═CH—(CO)_(k1)-Phe-(O)_(k2)—, Phe-CH═CH—, HOOC—, OCN—, and W⁴W⁵W⁶Si—,with W¹ being H, F, Cl, CN, CF₃, phenyl or alkyl with 1 to 5 C-atoms, inparticular H, C₁ or CH₃, W² and W³ being independently of each other Hor alkyl with 1 to 5 C-atoms, in particular H, methyl, ethyl orn-propyl, W⁴, W⁵ and W⁶ being independently of each other Cl, oxaalkylor oxacarbonylalkyl with 1 to 5 C-atoms, W⁷ and W⁸ being independentlyof each other H, Cl or alkyl with 1 to 5 C-atoms, Phe being1,4-phenylene that is optionally substituted by one or more groups L asdefined above, k₁, k₂ and k₃ being independently of each other 0 or 1,k₃ preferably being 1, and k₄ being an integer from 1 to 10.

Alternatively P is a protected derivative of these groups which isnon-reactive under the conditions described for the process according tothe present invention. Suitable protective groups are known to theordinary expert and described in the literature, for example in Green,“Protective Groups in Organic Synthesis”, John Wiley and Sons, New York(1981), like for example acetals or ketals.

Especially preferred groups P are CH₂═CH—CO—O—, CH₂═C(CH₃)—CO—O—,CH₂═CF—CO—O—, CH₂═CH—O—, (CH₂═CH)₂CH—O—CO—, (CH₂═CH)₂CH—O—, and

or protected derivatives thereof. Further preferred groups P areselected from the group consisting of vinyloxy, acrylate, methacrylate,fluoroacrylate, chloracrylate, oxetan and epoxy groups, very preferablyfrom an acrylate or methacrylate group.

Polymerisation of group P can be carried out according to methods thatare known to the ordinary expert and described in the literature, forexample in D. J. Broer; G. Challa; G. N. Mol, Macromol. Chem., 1991,192, 59.

The term “spacer group” is known in prior art and suitable spacer groupsSp are known to the ordinary expert (see e.g. Pure Appl. Chem. 73(5),888 (2001). The spacer group Sp is preferably of formula Sp′-X′, suchthat P-Sp- is P-Sp′-X¹—, wherein

-   Sp′ is alkylene with up to 30 C atoms which is unsubstituted or    mono- or polysubstituted by F, Cl, Br, I or CN, it being also    possible for one or more non-adjacent CH₂ groups to be replaced, in    each case independently from one another, by —O—, —S—, —NH—, —NR⁰—,    —SiR⁰R⁰⁰—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or    —C≡C— in such a manner that O and/or S atoms are not linked directly    to one another,-   X′ is —O—, —S—, —CO—, —COO—, —OCO—, —O—OCO—, —CO—NR⁰—, —NR⁰—CO—,    —NR⁰—CO—NR⁰⁰—, —OCH₂—, —CH₂O—, —SCH₂—, —CH₂S—, —CF₂O—, —OCF₂—,    —CF₂S—, —SCF₂—, —CF₂CH₂—, —CH₂CF₂—, —CF₂CF₂—, —CH═N—, —N═CH—, —N═N—,    —CH═CR⁰—, —CY¹═CY²—, —C≡C—, —CH═CH—OCO—, —OCO—CH═CH— or a single    bond,-   R⁰ and R⁰⁰ are independently of each other H or alkyl with 1 to 12    C-atoms, and-   Y¹ and Y² are independently of each other H, F, Cl or CN.-   X′ is preferably —O—, —S—, —OCH₂—, —CH₂O—, —SCH₂—, —CH₂S—, —CF₂O—,    —OCF₂—, —CF₂S—, —SCF₂—, —CH₂CH₂—, —CF₂CH₂—, —CH₂CF₂—, —CF₂CF₂—,    —CH═N—, —N═CH—, —N═N—, —CH═CR⁰—, —CY¹═CY²—, —C≡C— or a single bond,    in particular —O—, —S—, —C≡C—, —CY¹═CY²— or a single bond. In    another preferred embodiment X′ is a group that is able to form a    conjugated system, such as —C≡C— or —CY¹═CY²—, or a single bond.

Typical groups Sp′ are, for example, —(CH₂)_(p)—,—(CH₂CH₂O)_(q)—CH₂CH₂—, —CH₂CH₂—S—CH₂CH₂— or —CH₂CH₂—NH—CH₂CH₂— or—(SiR⁰R⁰⁰—O)_(p)—, with p being an integer from 2 to 12, q being aninteger from 1 to 3 and R⁰ and R⁰⁰ having the meanings given above.

Preferred groups Sp′ are ethylene, propylene, butylene, pentylene,hexylene, heptylene, octylene, nonylene, decylene, undecylene,dodecylene, octadecylene, ethyleneoxyethylene, methyleneoxybutylene,ethylene-thioethylene, ethylene-N-methyl-iminoethylene,1-methylalkylene, ethenylene, propenylene and butenylene for example.

The units of formula I are selected from the following formulae:

wherein R and R^(x) have the meanings given in formula I or one of thepreferred meanings as given above and below.

The polymers containing units of formula I, especially those of formulaII, are preferably selected of formula IIaR²—[(Ar¹—U—Ar²)_(x)—(Ar³)_(y)]_(n)—R³  IIawherein U, Ar¹⁻³, n, x and y have the meanings of formula I and II, andR² and R³ have independently of each other one of the meanings of R¹,

-   -   preferably halogen, or denote H, —CH₂Cl, —CHO, —CH═CH₂,        —SiR′R″R′″, —SnR′R″R′″, —BR′R″, —B(OR′)(OR″), —B(OH)₂, or P-Sp,        wherein P and Sp are as defined in formula I, and R′, R″ and R′″        have independently of each other one of the meanings of R⁰ given        in formula I, and two of R′, R″ and R′″ may also form a ring        together with the hetero atom to which they are attached.

In the polymers according to the present invention, the total number ofrepeating units n is preferably 5, very preferably 10, most preferably50, and preferably up to 500, very preferably up to 1,000, mostpreferably up to 2,000, including any combination of the aforementionedlower and upper limits of n.

The polymers of the present invention include homopolymers andcopolymers, like statistical or random copolymers, alternatingcopolymers and block copolymers, as well as combinations thereof.

Block copolymers may for example comprise or consist of one or moreblocks formed by units of formula I and one or more blocks formed byunits Ar³, wherein Ar³ has one of the meanings as described above andbelow.

Another aspect of the invention relates to monomers of formula IaR²—U—R³  Iawherein U is a unit of formula I, I1 or I2, or selected from itspreferred subformulae or preferred meanings as described above andbelow, and R² and R³ have the meanings given in formula IIa.

Especially preferred are monomers of formula Ia wherein R² and R³ are,preferably independently of each other, selected from the groupconsisting of Cl, Br, I, O-tosylate, O-triflate, O-mesylate,O-nonaflate, —SiMe₂F, —SiMeF₂, —O—SO₂Z¹, —B(OZ²)₂, —CZ³═C(Z³)₂, —C≡CHand —Sn(Z⁴)₃, wherein Z¹⁻⁴ are selected from the group consisting ofalkyl and aryl, each being optionally substituted, and two groups Z² mayalso form a cyclic group.

Preferably the repeating units of formula I, and the monomers of formulaIa and polymers of formula II and IIa containing them, are selected fromthe following list of preferred embodiments:

-   -   x is 1 and y is 0, thereby forming a repeating unit [Ar¹—U—Ar²],    -   x is 1 and y is 1, thereby forming a repeating unit        [Ar¹—U—Ar²—Ar³],    -   Ar¹ and Ar² are selected from 1,4-phenylene, thiophene-2,5-diyl,        thiazole-2,5-diyl, selenophene-2,5-diyl, furan-2,5-diyl,        thieno[3,2-b]thiophene-2,5-diyl,        thieno[2,3-b]thiophene-2,5-diyl,        selenopheno[3,2-b]selenophene-2,5-diyl,        selenopheno[2,3-b]selenophene-2,5-diyl,        selenopheno[3,2-b]thiophene-2,5-diyl, or        selenopheno[2,3-b]thiophene-2,5-diyl, all of which are        unsubstituted, or mono- or polysubstituted, preferably with R,        R¹ or R^(y) as defined above and below,    -   Ar³ is selected from 1,4-phenylene, thiophene-2,5-diyl,        selenophene-2,5-diyl, thieno[3,2-b]thiophene-2,5-diyl,        thieno[2,3-b]thiophene-2,5-diyl,        selenopheno[3,2-b]selenophene-2,5-diyl,        selenopheno[2,3-b]selenophene-2,5-diyl,        selenopheno[3,2-b]thiophene-2,5-diyl,        selenopheno[2,3-b]thiophene-2,5-diyl,        benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl, 2,2-dithiophene,        2,2-diselenophene, dithieno[3,2-b:2′,3′-d]silole-5,5-diyl,        4H-cyclopenta[2,1-b:3,4-b′]dithiophene-2,6-diyl,        carbazole-2,7-diyl, fluorene-2,7-diyl,        indaceno[1,2-b:5,6-b′]dithiophene-2,7-diyl,        benzo[1″,2″:4,5;4″,5″:4′,5′]bis(silolo[3,2-b:3′,2′-b]thiophene)-2,7-diyl,        phenanthro[1,10,9,8-c,d,e,f,g]carbazole-2,7-diyl,        benzo[2,1,3]thiadiazole-4,7-diyl,        benzo[2,1,3]selenadiazole-4,7-diyl,        benzo[2,1,3]oxadiazole-4,7-diyl, 2H-benzotriazole-4,7-diyl,        3,4-difluorothiophene-2,5-diyl, thieno[3,4-b]pyrazine-2,5-diyl,        quinoxaline-5,8-diyl, thieno[3,4-b]thiophene-4,6-diyl,        thieno[3,4-b]thiophene-6,4-diyl,        3,6-di-thien-2-yl-pyrrolo[3,4-c]pyrrole-1,4-dione, or        [1,3]thiazolo[5,4-d][1,3]thiazole-2,5-diyl, all of which are        unsubstituted, or mono- or polysubstituted, preferably with R,        R¹ or R^(y) as defined above and below,    -   n is at least 5, preferably at least 10, very preferably at        least 50, and up to 2,000, preferably up to 500.    -   Mw is at least 5,000, preferably at least 8,000, very preferably        at least 10,000, and preferably up to 300,000, very preferably        up to 100,000,    -   R is H,    -   R is different from H,    -   R is primary alkyl or alkoxy with 1 to 30 C atoms, secondary        alkyl or alkoxy with 3 to 30 C atoms, or tertiary alkyl or        alkoxy with 4 to 30 C atoms, wherein in all these groups one or        more H atoms are optionally replaced by F,    -   R is aryl, heteroaryl, aryloxy or heteroaryloxy, each of which        is optionally alkylated or alkoxylated and has 4 to 30 ring        atoms,    -   R is F, Cl, Br, I, CN, —CO—R^(y), —CO—O—R^(y), or —O—CO—R^(y),        very preferably —CO—R^(y) or —CO—O—R^(y), wherein R^(y) is        straight-chain, branched or cyclic alkyl with 1 to 30 C atoms,        in which one or more non-adjacent C atoms are optionally        replaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —CR⁰═CR⁰⁰—        or —C≡C— and in which one or more H atoms are optionally        replaced by F, Cl, Br, I or CN, or R^(y) is aryl, aryloxy,        heteroaryl or heteroaryloxy having 4 to 30 ring atoms that is        unsubstituted or substituted by one or more non-aromatic groups        R¹ as defined in formula I,    -   R^(y) is primary alkyl with 1 to 30 C atoms, very preferably        with 1 to 15 C atoms, secondary alkyl with 3 to 30 C atoms, or        tertiary alkyl with 4 to 30 C atoms, wherein in all these groups        one or more H atoms are optionally replaced by F,    -   R^(y) is —(CH₂)_(n)—CR^(a)R^(b)R^(c), wherein o is 0, 1, 2, 3, 4        or 5, very preferably 0, 1 or 2, and R^(a), R^(b) and R^(c) are        independently of each other C₁-C₁₂-alkyl, very preferably        C₁-C₈-alkyl, which is optionally substituted by one or more F        atoms, and wherein optionally one of R^(a), R^(b) and R^(c) is        H,    -   R^(y) is aryl, heteroaryl, aryloxy or heteroaryloxy, each of        which is optionally alkylated or alkoxylated and has 4 to 30        ring atoms,    -   R^(x) is alkyl with 1 to 30 C atoms,    -   R^(x) is CO—R^(y), —CO—O—R^(y), or —O—CO—R^(y), very preferably        —CO—R^(y) or —CO—O—R^(y), wherein R^(y) is straight-chain,        branched or cyclic alkyl with 1 to 30 C atoms, in which one or        more non-adjacent C atoms are optionally replaced by —O—, —S—,        —CO—, —CO—O—, —O—CO—, —O—CO—O—, —CR⁰═CR⁰⁰— or —C≡C— and in which        one or more H atoms are optionally replaced by F, Cl, Br, I or        ON, or R^(y) is aryl, aryloxy, heteroaryl or heteroaryloxy        having 4 to 30 ring atoms that is unsubstituted or substituted        by one or more non-aromatic groups R¹ as defined in formula I    -   R⁰ and R⁰⁰ are selected from H or C₁-C₁₀-alkyl,    -   R² and R³ are selected from H, halogen, —CH₂Cl, —CHO,        —CH═CH₂—SiR′R″R′″, —SnR′R″R′″, —BR′R″, —B(OR′)(OR″), —B(OH)₂,        P-Sp, C₁-C₂₀-alkyl, C₁-C₂₀-alkoxy, C₂-C₂₀-alkenyl,        C₁-C₂₀-fluoroalkyl and optionally substituted aryl or        heteroaryl,    -   R² and R³ are, preferably independently of each other, selected        from the group consisting of Cl, Br, I, O-tosylate, O-triflate,        O-mesylate, O-nonaflate, —SiMe₂F, —SiMeF₂, —O—SO₂Z′, —B(OZ²)₂,        —CZ³═C(Z⁴)₂, —C≡CH and —Sn(Z⁴)₃, wherein Z¹⁻⁴ are selected from        the group consisting of alkyl and aryl, each being optionally        substituted, and two groups Z² may also form a cyclic group,        very preferably from Br,    -   R¹ is alkyl, alkoxy, alkylcarbonyl, alkylcarbonyloxy or        alkoxycarbonyl with 1 to 30 C atoms, wherein one or more H atoms        are optionally replaced by F,    -   R¹ is H,    -   R is P-Sp-.

Preferred polymers of formula II are selected from the followingformulae:

wherein X, R and n are as defined in formula I or have one of thepreferred meanings as given above and below.

Preferred polymers of formula IIa are selected of the formulaR²-chain-R³wherein “chain” is a polymer chain selected from above formulae II1-,and R² and R³ have one of the meanings of R² and R³ given in formula IIaor one of the preferred meanings of R² and R³ given above and below.

The polymers of the present invention can be synthesized according to orin analogy to methods that are known to the skilled person and aredescribed in the literature. Other methods of preparation can be takenfrom the examples. For example, they can be suitably prepared byaryl-aryl coupling reactions, such as Yamamoto coupling, Suzukicoupling, Stille coupling, Sonogashira coupling, Heck coupling orBuchwald coupling. Suzuki coupling and Yamamoto coupling are especiallypreferred.

The monomers which are polymerised to form the repeat units of thepolymers can be prepared according to methods which are known to theperson skilled in the art.

Preferably the polymers are prepared from monomers of formula Ia or itspreferred embodiments as described above and below.

Another aspect of the invention is a process for preparing a polymer bycoupling one or more identical or different monomeric units of formula Ior monomers of formula Ia with each other and/or with one or morecomonomers in a polymerisation reaction, preferably in an aryl-arylcoupling reaction.

Suitable and preferred comonomers are those of the formulaR²—Ar³—R³wherein Ar³, R² and R³ are as defined above.

Preferred methods for polymerisation are those leading to C—C-couplingor C—N-coupling, like Suzuki polymerisation, as described for example inWO 00/53656, Yamamoto polymerisation, as described in for example in T.Yamamoto et al., Progress in Polymer Science 1993, 17, 1153-1205 or inWO 2004/022626 A1, and Stille coupling. For example, when synthesizing alinear polymer by Yamamoto polymerisation, monomers as described abovehaving two reactive halide groups R² and R³ is preferably used. Whensynthesizing a linear polymer by Suzuki polymerisation, preferably amonomer as described above is used wherein at least one reactive groupR² or R³ is a boronic acid or boronic acid derivative group.

Suzuki polymerisation may be used to prepare homopolymers as well asstatistical, alternating and block random copolymers. Statistical orblock copolymers can be prepared for example from the above monomers offormula Ia wherein one of the reactive groups R² and R³ is halogen andthe other reactive group is a boronic acid or boronic acid derivativegroup. The synthesis of statistical, alternating and block copolymers isdescribed in detail for example in WO 03/048225 A2 or WO 2005/014688 A2.

Suzuki polymerisation employs a Pd(0) complex or a Pd(II) salt.Preferred Pd(0) complexes are those bearing at least one phosphineligand such as Pd(Ph₃P)₄. Another preferred phosphine ligand istris(ortho-tolyl)phosphine, i.e. Pd(o-Tol)₄. Preferred Pd(II) saltsinclude palladium acetate, i.e. Pd(OAc)₂. Suzuki polymerisation isperformed in the presence of a base, for example sodium carbonate,potassium phosphate or an organic base such as tetraethylammoniumcarbonate. Yamamoto polymerisation employs a Ni(0) complex, for examplebis(1,5-cyclooctadienyl) nickel(0).

As alternatives to halogens as described above, leaving groups offormula —O—SO₂Z¹ can be used wherein Z¹ is as described above.Particular examples of such leaving groups are tosylate, mesylate andtriflate.

Especially suitable and preferred synthesis methods of the repeatingunits and monomers of formula I and Ia, and their homo- and co-polymersof formula II and IIa, are illustrated in the synthesis schemes shownhereinafter, wherein R, Ar¹, Ar² and Ar^(a) are as defined in formula Iand II.

The synthesis of the 3,7-diaryl-benzo[1,2-b;4,5-b′]difuran-2,6-dionecore can be carried out as illustrated in Scheme 1.

The synthesis of the 3,7-diaryl-benzo[1,2-b;4,5-b′]dipyrrole-2,6-dionecore can be carried out as described in Scheme 2.

The generic synthesis of3,7-dibromo-benzo[1,2-b;4,5-b′]dithiophene-2,6-dione is described inNakatsuka, M. et al., Chemistry Letters, 1983, 905-908 and can becarried out as described in Scheme 3.

The further functionalisation of the3,7-diaryl-benzo[1,2-b;4,5-b′]difuran-2,6-dione core (X═O, R=alkyl/arylor H), 3,7-diaryl-benzo[1,2-b;4,5-b′]dithiophene-2,6-dione core (X═S,R=alkyl/aryl or H) and 3,7-diaryl-benzo[1,2-b;4,5-b′]dipyrrole-2,6-dionecore (X═N-Alkyl or N-Aryl, R═H) can be carried out as described inScheme 4.

The synthesis of homopolymers of3,7-diaryl-benzo[1,2-b;4,5-b′]difuran-2,6-dione (X═O, R=alkyl/aryl orH), 3,7-diaryl-benzo[1,2-b;4,5-b′]dithiophene-2,6-dione core (X═S,R=alkyl/aryl or H) and 3,7-diaryl-benzo[1,2-b;4,5-b′]dipyrrole-2,6-dione(X═N-Alkyl or N-Aryl, R═H) can be carried out as described in Scheme 5.

The synthesis of alternating co-polymers of3,7-diaryl-benzo[1,2-b;4,5-b′]difuran-2,6-dione (X═O, R=alkyl/aryl orH), 3,7-diaryl-benzo[1,2-b;4,5-b′]dithiophene-2,6-dione core (X═S,R=alkyl/aryl or H) and 3,7-diaryl-benzo[1,2-b;4,5-b′]dipyrrole-2,6-dione(X═N-Alkyl or N-Aryl, R═H) can be carried out as described in Scheme 6.

The novel methods of preparing monomers and polymers as described aboveand below are another aspect of the invention.

The polymers according to the present invention can also be used inmixtures or polymer blends, for example together with monomericcompounds or together with other polymers having charge-transport,semiconducting, electrically conducting, photoconducting and/or lightemitting semiconducting properties, or for example with polymers havinghole blocking or electron blocking properties for use as interlayers orcharge blocking layers in OLED devices. Thus, another aspect of theinvention relates to a polymer blend comprising one or more polymersaccording to the present invention and one or more further polymershaving one or more of the above-mentioned properties. These blends canbe prepared by conventional methods that are described in prior art andknown to the skilled person. Typically the polymers are mixed with eachother or dissolved in suitable solvents and the solutions combined.

Another aspect of the invention relates to a formulation comprising oneor more polymers, mixtures or polymer blends as described above andbelow and one or more organic solvents.

Preferred solvents are aliphatic hydrocarbons, chlorinated hydrocarbons,aromatic hydrocarbons, ketones, ethers and mixtures thereof. Additionalsolvents which can be used include 1,2,4-trimethylbenzene,1,2,3,4-tetramethyl benzene, pentylbenzene, mesitylene, cumene, cymene,cyclohexylbenzene, diethylbenzene, tetralin, decalin, 2,6-lutidine,2-fluoro-m-xylene, 3-fluoro-o-xylene, 2-chlorobenzotrifluoride,dimethylformamide, 2-chloro-6-fluorotoluene, 2-fluoroanisole, anisole,2,3-dimethylpyrazine, 4-fluoroanisole, 3-fluoroanisole,3-trifluoro-methylanisole, 2-methylanisole, phenetol, 4-methylanisole,3-methylanisole, 4-fluoro-3-methylanisole, 2-fluorobenzonitrile,4-fluoroveratrol, 2,6-dimethylanisole, 3-fluorobenzonitrile,2,5-dimethylanisole, 2,4-dimethylanisole, benzonitrile,3,5-dimethylanisole, N,N-dimethylaniline, ethyl benzoate,1-fluoro-3,5-dimethoxybenzene, 1-methylnaphthalene,N-methylpyrrolidinone, 3-fluorobenzotrifluoride, benzotrifluoride,benzotrifluoride, diosane, trifluoromethoxybenzene,4-fluorobenzotrifluoride, 3-fluoropyridine, toluene, 2-fluorotoluene,2-fluorobenzotrifluoride, 3-fluorotoluene, 4-isopropylbiphenyl, phenylether, pyridine, 4-fluorotoluene, 2,5-difluorotoluene,1-chloro-2,4-difluorobenzene, 2-fluoropyridine, 3-chlorofluorobenzene,3-chlorofluorobenzene, 1-chloro-2,5-difluorobenzene,4-chlorofluorobenzene, chlorobenzene, o-dichlorobenzene,2-chlorofluorobenzene, p-xylene, m-xylene, o-xylene or mixture of o-,m-, and p-isomers. Solvents with relatively low polarity are generallypreferred. For inkjet printing solvents with high boiling temperaturesand solvent mixtures are preferred. For spin coating alkylated benzeneslike xylene and toluene are preferred.

Examples of especially preferred solvents include, without limitation,dichloromethane, trichloromethane, monochlorobenzene, o-dichlorobenzene,tetrahydrofuran, anisole, morpholine, toluene, o-xylene, m-xylene,p-xylene, 1,4-dioxane, acetone, methylethylketone, 1,2-dichloroethane,1,1,1-trichloroethane, 1,1,2,2-tetrachloroethane, ethyl acetate, n-butylacetate, dimethylformamide, dimethylacetamide, dimethylsulfoxide,tetraline, decaline, indane, methyl benzoate, ethyl benzoate, mesityleneand/or mixtures thereof.

The concentration of the polymers in the solution is preferably 0.1 to10% by weight, more preferably 0.5 to 5% by weight. Optionally, thesolution also comprises one or more binders to adjust the rheologicalproperties, as described for example in WO 2005/055248 A1.

After the appropriate mixing and ageing, solutions are evaluated as oneof the following categories: complete solution, borderline solution orinsoluble. The contour line is drawn to outline the solubilityparameter-hydrogen bonding limits dividing solubility and insolubility.‘Complete’ solvents falling within the solubility area can be chosenfrom literature values such as published in “Crowley, J. D., Teague, G.S. Jr and Lowe, J. W. Jr., Journal of Paint Technology, 38, No 496, 296(1966)”. Solvent blends may also be used and can be identified asdescribed in “Solvents, W. H. Ellis, Federation of Societies forCoatings Technology, p 9-10, 1986”. Such a procedure may lead to a blendof ‘non’ solvents that will dissolve both the polymers of the presentinvention, although it is desirable to have at least one true solvent ina blend.

The polymers according to the present invention can also be used inpatterned OSC layers in the devices as described above and below. Forapplications in modern microelectronics it is generally desirable togenerate small structures or patterns to reduce cost (more devices/unitarea), and power consumption. Patterning of thin layers comprising apolymer according to the present invention can be carried out forexample by photolithography, electron beam lithography or laserpatterning.

For use as thin layers in electronic or electrooptical devices thepolymers, polymer blends or formulations of the present invention may bedeposited by any suitable method. Liquid coating of devices is moredesirable than vacuum deposition techniques. Solution deposition methodsare especially preferred. The formulations of the present inventionenable the use of a number of liquid coating techniques. Preferreddeposition techniques include, without limitation, dip coating, spincoating, ink jet printing, letter-press printing, screen printing,doctor blade coating, roller printing, reverse-roller printing, offsetlithography printing, flexographic printing, web printing, spraycoating, brush coating or pad printing. Ink-jet printing is particularlypreferred as it allows high resolution layers and devices to beprepared.

Selected formulations of the present invention may be applied toprefabricated device substrates by ink jet printing or microdispensing.Preferably industrial piezoelectric print heads such as but not limitedto those supplied by Aprion, Hitachi-Koki, InkJet Technology, On TargetTechnology, Picojet, Spectra, Trident, Xaar may be used to apply theorganic semiconductor layer to a substrate. Additionally semi-industrialheads such as those manufactured by Brother, Epson, Konica, SeikoInstruments Toshiba TEC or single nozzle microdispensers such as thoseproduced by Microdrop and Microfab may be used.

In order to be applied by ink jet printing or microdispensing, thepolymers should be first dissolved in a suitable solvent. Solvents mustfulfil the requirements stated above and must not have any detrimentaleffect on the chosen print head. Additionally, solvents should haveboiling points>100° C., preferably >140° C. and more preferably >150° C.in order to prevent operability problems caused by the solution dryingout inside the print head. Apart from the solvents method above,suitable solvents include substituted and non-substituted xylenederivatives, di-C₁₋₂-alkyl formamide, substituted and non-substitutedanisoles and other phenol-ether derivatives, substituted heterocyclessuch as substituted pyridines, pyrazines, pyrimidines, pyrrolidinones,substituted and non-substituted N,N-di-C₁₋₂-alkylanilines and otherfluorinated or chlorinated aromatics.

A preferred solvent for depositing a polymer according to the presentinvention by ink jet printing comprises a benzene derivative which has abenzene ring substituted by one or more substituents wherein the totalnumber of carbon atoms among the one or more substituents is at leastthree. For example, the benzene derivative may be substituted with apropyl group or three methyl groups, in either case there being at leastthree carbon atoms in total. Such a solvent enables an ink jet fluid tobe formed comprising the solvent with the polymer, which reduces orprevents clogging of the jets and separation of the components duringspraying. The solvent(s) may include those selected from the followinglist of examples: dodecylbenzene, 1-methyl-4-tert-butylbenzene,terpineol limonene, isodurene, terpinolene, cymene, diethylbenzene. Thesolvent may be a solvent mixture, that is a combination of two or moresolvents, each solvent preferably having a boiling point>100° C., morepreferably >140° C. Such solvent(s) also enhance film formation in thelayer deposited and reduce defects in the layer.

The ink jet fluid (that is mixture of solvent, binder and semiconductingcompound) preferably has a viscosity at 20° C. of 1-100 mPa·s, morepreferably 1-50 mPa·s and most preferably 1-30 mPa·s.

The polymers or formulations according to the present invention canadditionally comprise one or more further components or additivesselected for for example from surface-active compounds, lubricatingagents, wetting agents, dispersing agents, hydrophobing agents, adhesiveagents, flow improvers, defoaming agents, deaerators, diluents which maybe reactive or non-reactive, auxiliaries, colourants, dyes or pigments,sensitizers, stabilizers, nanoparticles or inhibitors.

The polymers according to the present invention are useful as chargetransport, semiconducting, electrically conducting, photoconducting orlight mitting materials in optical, electrooptical, electronic,electroluminescent or photoluminescent components or devices. In thesedevices, the polymers of the present invention are typically applied asthin layers or films.

Thus, the present invention also provides the use of the semiconductingpolymer, polymer blend, formulation or layer in an electronic device.The formulation may be used as a high mobility semiconducting materialin various devices and apparatus. The formulation may be used, forexample, in the form of a semiconducting layer or film. Accordingly, inanother aspect, the present invention provides a semiconducting layerfor use in an electronic device, the layer comprising a polymer, polymerblend or formulation according to the invention. The layer or film maybe less than about 30 microns. For various electronic deviceapplications, the thickness may be less than about 1 micron thick. Thelayer may be deposited, for example on a part of an electronic device,by any of the aforementioned solution coating or printing techniques.

The invention additionally provides an electronic device comprising apolymer, polymer blend, formulation or organic semiconducting layeraccording to the present invention. Especially preferred devices areOFETs, TFTs, ICs, logic circuits, capacitors, RFID tags, OLEDs, OLETs,OPEDs, OPVs, solar cells, laser diodes, photoconductors, photodetectors,electrophotographic devices, electrophotographic recording devices,organic memory devices, sensor devices, charge injection layers,Schottky diodes, planarising layers, antistatic films, conductingsubstrates and conducting patterns.

Especially preferred electronic device are OFETs, OLEDs and OPV devices,in particular bulk heterojunction (BHJ) OPV devices. In an OFET, forexample, the active semiconductor channel between the drain and sourcemay comprise the layer of the invention. As another example, in an OLEDdevice, the charge (hole or electron) injection or transport layer maycomprise the layer of the invention.

For use in OPV devices the polymer according to the present invention ispreferably used in a formulation that comprises or contains, morepreferably consists essentially of, very preferably exclusively of, ap-type (electron donor) semiconductor and an n-type (electron acceptor)semiconductor. The p-type semiconductor is constituted by a polymeraccording to the present invention. The n-type semiconductor can be aninorganic material such as zinc oxide or cadmium selenide, or an organicmaterial such as a fullerene derivate, for example (6,6)-phenyl-butyricacid methyl ester derivatized methano C₆₀ fullerene, also known as“PCBM” or “C₆₀PCBM”, as disclosed for example in G. Yu, J. Gao, J. C.Hummelen, F. Wudl, A. J. Heeger, Science 1995, Vol. 270, p. 1789 ff andhaving the structure shown below, or an structural analogous compoundwith e.g. a C₇₀ fullerene group (C₇₀PCBM), or a polymer (see for exampleCoakley, K. M. and McGehee, M. D. Chem. Mater. 2004, 16, 4533).

A preferred material of this type is a blend or mixture of a polymeraccording to the present invention with a C₆₀ or C₇₀ fullerene ormodified fullerene like PCBM. Preferably the ratio polymer:fullerene isfrom 2:1 to 1:2 by weight, more preferably from 1.2:1 to 1:1.2 byweight, most preferably 1:1 by weight. For the blended mixture, anoptional annealing step may be necessary to optimize blend morphologyand consequently OPV device performance.

The OPV device can for example be of any type known from the literature[see e.g. Waldauf et al., Appl. Phys. Lett. 89, 233517 (2006)].

A first preferred OPV device according to the invention comprises:

-   -   a low work function electrode (11) (for example a metal, such as        aluminum), and a high work function electrode (12) (for example        ITO), one of which is transparent,    -   a layer (13) (also referred to as “active layer”) comprising a        hole transporting material and an electron transporting        material, preferably selected from OSC materials, situated        between the electrodes (11,12); the active layer can exist for        example as a bilayer or two distinct layers or blend or mixture        of p-type and n-type semiconductor, forming a bulk heterjunction        (BHJ) (see for example Coakley, K. M. and McGehee, M. D. Chem.        Mater. 2004, 16, 4533),    -   an optional conducting polymer layer (14), for example        comprising a blend of PEDOT:PSS        (poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate)),        situated between the active layer (13) and the high work        function electrode (12), to modify the work function of the high        work function electrode to provide an ohmic contact for holes,    -   an optional coating (15) (for example of LiF) on the side of the        low workfunction electrode (11) facing the active layer (13), to        provide an ohmic contact for electrons.

A second preferred OPV device according to the invention is an invertedOPV device and comprises:

-   -   a low work function electrode (21) (for example a metal, such as        gold), and a high work function electrode (22) (for example        ITO), one of which is transparent,    -   a layer (23) (also referred to as “active layer”) comprising a        hole transporting material and an electron transporting        material, preferably selected from OSC materials, situated        between the electrodes (21,22); the active layer can exist for        example as a bilayer or two distinct layers or blend or mixture        of p-type and n-type semiconductor, forming a BHJ,    -   an optional conducting polymer layer (24), for example        comprising a blend of PEDOT:PSS, situated between the active        layer (23) and the low work function electrode (21) to provide        an ohmic contact for electrons,    -   an optional coating (25) (for example of TiO_(x)) on the side of        the high workfunction electrode (22) facing the active layer        (23), to provide an ohmic contact for holes.

In the OPV devices of the present invent invention the p-type and n-typesemiconductor materials are preferably selected from the materials, likethe polymer/fullerene systems, as described above. If the bilayer is ablend an optional annealing step may be necessary to optimize deviceperformance.

The compound, formulation and layer of the present invention are alsosuitable for use in an OFET as the semiconducting channel. Accordingly,the invention also provides an OFET comprising a gate electrode, aninsulating (or gate insulator) layer, a source electrode, a drainelectrode and an organic semiconducting channel connecting the sourceand drain electrodes, wherein the organic semiconducting channelcomprises a polymer, polymer blend, formulation or organicsemiconducting layer according to the present invention. Other featuresof the OFET are well known to those skilled in the art.

OFETs where an OSC material is arranged as a thin film between a gatedielectric and a drain and a source electrode, are generally known, andare described for example in U.S. Pat. No. 5,892,244, U.S. Pat. No.5,998,804, U.S. Pat. No. 6,723,394 and in the references cited in thebackground section. Due to the advantages, like low cost productionusing the solubility properties of the compounds according to theinvention and thus the processability of large surfaces, preferredapplications of these FETs are such as integrated circuitry, TFTdisplays and security applications.

The gate, source and drain electrodes and the insulating andsemiconducting layer in the OFET device may be arranged in any sequence,provided that the source and drain electrode are separated from the gateelectrode by the insulating layer, the gate electrode and thesemiconductor layer both contact the insulating layer, and the sourceelectrode and the drain electrode both contact the semiconducting layer.

An OFET device according to the present invention preferably comprises:

-   -   a source electrode,    -   a drain electrode,    -   a gate electrode,    -   a semiconducting layer,    -   one or more gate insulator layers,    -   optionally a substrate.        wherein the semiconductor layer preferably comprises a polymer,        polymer blend or formulation as described above and below.

The OFET device can be a top gate device or a bottom gate device.Suitable structures and manufacturing methods of an OFET device areknown to the skilled in the art and are described in the literature, forexample in US 2007/0102696 A1.

The gate insulator layer preferably comprises a fluoropolymer, like e.g.the commercially available Cytop 809M® or Cytop 107M® (from AsahiGlass). Preferably the gate insulator layer is deposited, e.g. byspin-coating, doctor blading, wire bar coating, spray or dip coating orother known methods, from a formulation comprising an insulator materialand one or more solvents with one or more fluoro atoms (fluorosolvents),preferably a perfluorosolvent. A suitable perfluorosolvent is e.g. FC75®(available from Acros, catalogue number 12380). Other suitablefluoropolymers and fluorosolvents are known in prior art, like forexample the perfluoropolymers Teflon AF®, 1600 or 2400 (from DuPont) orFluoropel® (from Cytonix) or the perfluorosolvent FC 43® (Acros, No.12377). Especially preferred are organic dielectric materials having alow permittivity (or dielectric constant) from 1.0 to 5.0, verypreferably from 1.8 to 4.0 (“low k materials”), as disclosed for examplein US 2007/0102696 A1 or U.S. Pat. No. 7,095,044.

In security applications, OFETs and other devices with semiconductingmaterials according to the present invention, like transistors ordiodes, can be used for RFID tags or security markings to authenticateand prevent counterfeiting of documents of value like banknotes, creditcards or ID cards, national ID documents, licenses or any product withmonetary value, like stamps, tickets, shares, cheques etc.

Alternatively, the materials according to the invention can be used inOLEDs, e.g. as the active display material in a flat panel displayapplications, or as backlight of a flat panel display like e.g. a liquidcrystal display. Common OLEDs are realized using multilayer structures.An emission layer is generally sandwiched between one or moreelectron-transport and/or hole-transport layers. By applying an electricvoltage electrons and holes as charge carriers move towards the emissionlayer where their recombination leads to the excitation and henceluminescence of the lumophor units contained in the emission layer. Theinventive compounds, materials and films may be employed in one or moreof the charge transport layers and/or in the emission layer,corresponding to their electrical and/or optical properties. Furthermoretheir use within the emission layer is especially advantageous, if thecompounds, materials and films according to the invention showelectroluminescent properties themselves or comprise electroluminescentgroups or compounds. The selection, characterization as well as theprocessing of suitable monomeric, oligomeric and polymeric compounds ormaterials for the use in OLEDs is generally known by a person skilled inthe art, see, e.g., Meerholz, Synthetic Materials, 111-112, 2000, 31-34,Alcala, J. Appl. Phys., 88, 2000, 7124-7128 and the literature citedtherein.

According to another use, the materials according to this invention,especially those showing photoluminescent properties, may be employed asmaterials of light sources, e.g. in display devices, as described in EP0 889 350 A1 or by C. Weder et al., Science, 279, 1998, 835-837.

A further aspect of the invention relates to both the oxidised andreduced form of the compounds according to this invention. Either lossor gain of electrons results in formation of a highly delocalised ionicform, which is of high conductivity. This can occur on exposure tocommon dopants. Suitable dopants and methods of doping are known tothose skilled in the art, e.g. from EP 0 528 662, U.S. Pat. No.5,198,153 or WO 96/21659.

The doping process typically implies treatment of the semiconductormaterial with an oxidating or reducing agent in a redox reaction to formdelocalised ionic centres in the material, with the correspondingcounterions derived from the applied dopants. Suitable doping methodscomprise for example exposure to a doping vapor in the atmosphericpressure or at a reduced pressure, electrochemical doping in a solutioncontaining a dopant, bringing a dopant into contact with thesemiconductor material to be thermally diffused, and ion-implantation ofthe dopant into the semiconductor material.

When electrons are used as carriers, suitable dopants are for examplehalogens (e.g., I₂, Cl₂, Br₂, ICl, ICl₃, IBr and IF), Lewis acids (e.g.,PF₅, AsF₅, SbF₅, BF₃, BCl₃, SbCl₅, BBr₃ and SO₃), protonic acids,organic acids, or amino acids (e.g., HF, HCl, HNO₃, H₂SO₄, HClO₄, FSO₃Hand ClSO₃H), transition metal compounds (e.g., FeCl₃, FeOCl, Fe(ClO₄)₃,Fe(4-CH₃C₆H₄SO₃)₃, TiCl₄, ZrCl₄, HfCl₄, NbF₅, NbCl₅, TaCl₅, MoF₅, MoCl₅,WF₅, WCl₆, UF₆ and LnCl₃ (wherein Ln is a lanthanoid), anions (e.g.,Cl⁻, Br⁻, I⁻, I₃ ⁻, HSO₄ ⁻, SO₄ ²⁻, NO₃ ⁻, ClO₄ ⁻, BF₄ ⁻, PF₆ ⁻, AsF₆ ⁻,SbF₆ ⁻, FeCl₄ ⁻, Fe(CN)₆ ³⁻, and anions of various sulfonic acids, suchas aryl-SO₃ ⁻). When holes are used as carriers, examples of dopants arecations (e.g., H⁺, Li⁺, Na⁺, K⁺, Rb⁺ and Cs⁺), alkali metals (e.g., Li,Na, K, Rb, and Cs), alkaline-earth metals (e.g., Ca, Sr, and Ba), O₂,XeOF₄, (NO₂)+(SbF₆ ⁻), (NO₂ ⁺) (SbCl₆ ⁻), (NO₂)+(BF₄ ⁻), AgClO₄,H₂IrCl₆, La(NO₃)₃.6H₂O, FSO₂OOSO₂F, Eu, acetylcholine, R₄N⁺, (R is analkyl group), R₄P⁺ (R is an alkyl group), R₆As⁺ (R is an alkyl group),and R₃S⁺ (R is an alkyl group).

The conducting form of the compounds of the present invention can beused as an organic “metal” in applications including, but not limitedto, charge injection layers and ITO planarising layers in OLEDapplications, films for flat panel displays and touch screens,antistatic films, printed conductive substrates, patterns or tracts inelectronic applications such as printed circuit boards and condensers.

The compounds and formulations according to the present invention mayalso be suitable for use in organic plasmon-emitting diodes (OPEDs), asdescribed for example in Koller et al., Nature Photonics 2008 (publishedonline Sep. 28, 2008).

According to another use, the materials according to the presentinvention can be used alone or together with other materials in or asalignment layers in LCD or OLED devices, as described for example in US2003/0021913. The use of charge transport compounds according to thepresent invention can increase the electrical conductivity of thealignment layer. When used in an LCD, this increased electricalconductivity can reduce adverse residual dc effects in the switchableLCD cell and suppress image sticking or, for example in ferroelectricLCDs, reduce the residual charge produced by the switching of thespontaneous polarisation charge of the ferroelectric LCs. When used inan OLED device comprising a light emitting material provided onto thealignment layer, this increased electrical conductivity can enhance theelectroluminescence of the light emitting material. The compounds ormaterials according to the present invention having mesogenic or liquidcrystalline properties can form oriented anisotropic films as describedabove, which are especially useful as alignment layers to induce orenhance alignment in a liquid crystal medium provided onto saidanisotropic film. The materials according to the present invention mayalso be combined with photoisomerisable compounds and/or chromophoresfor use in or as photoalignment layers, as described in US 2003/0021913.

According to another use the materials according to the presentinvention, especially their water-soluble derivatives (for example withpolar or ionic side groups) or ionically doped forms, can be employed aschemical sensors or materials for detecting and discriminating DNAsequences. Such uses are described for example in L. Chen, D. W.McBranch, H. Wang, R. Helgeson, F. Wudl and D. G. Whitten, Proc. Natl.Acad. Sci. U.S.A. 1999, 96, 12287; D. Wang, X. Gong, P. S. Heeger, F.Rininsland, G. C. Bazan and A. J. Heeger, Proc. Natl. Acad. Sci. U.S.A.2002, 99, 49; N. DiCesare, M. R. Pinot, K. S. Schanze and J. R.Lakowicz, Langmuir 2002, 18, 7785; D. T. McQuade, A. E. Pullen, T. M.Swager, Chem. Rev. 2000, 100, 2537.

Unless the context clearly indicates otherwise, as used herein pluralforms of the terms herein are to be construed as including the singularform and vice versa.

Throughout the description and claims of this specification, the words“comprise” and “contain” and variations of the words, for example“comprising” and “comprises”, mean “including but not limited to”, andare not intended to (and do not) exclude other components.

It will be appreciated that variations to the foregoing embodiments ofthe invention can be made while still falling within the scope of theinvention. Each feature disclosed in this specification, unless statedotherwise, may be replaced by alternative features serving the same,equivalent or similar purpose. Thus, unless stated otherwise, eachfeature disclosed is one example only of a generic series of equivalentor similar features.

All of the features disclosed in this specification may be combined inany combination, except combinations where at least some of suchfeatures and/or steps are mutually exclusive. In particular, thepreferred features of the invention are applicable to all aspects of theinvention and may be used in any combination. Likewise, featuresdescribed in non-essential combinations may be used separately (not incombination).

It will be appreciated that many of the features described above,particularly of the preferred embodiments, are inventive in their ownright and not just as part of an embodiment of the present invention.Independent protection may be sought for these features in addition toor alternative to any invention presently claimed.

The invention will now be described in more detail by reference to thefollowing examples, which are illustrative only and do not limit thescope of the invention.

Example 12-(4-Bromo-phenyl)-N-{4-[2-(4-bromo-phenyl)-2-hydroxy-acetylamino]-phenyl}-2-hydroxy-acetamide(1.1)

In a 250 cm³ flask fitted with a consender and a reverse Dean-Starkapparatus, the (4-bromo-phenyl)-hydroxy-acetic acid (25.00 g, 108.2mmol) and 1,4-phenylenediamine (3.900 g, 36.07 mmol) are dissolved inchlorobenzene (100 cm³). The reaction mixture is heated to 132° C. whilethe generated water is distilled off the using the reverse Dean-Starkapparatus. After 21 hours, the reaction mixture is cooled down, theprecipitate is filtered off and washed with methanol to yield theproduct (18.21 g, Yield: 95%). NMR (1H, 300 MHz, CDCl₃): δ 9.90 (br,2H); 7.59 (s, 4H); 7.56 (d, J=8.5 Hz, 4H); 7.45 (d, J=8.5 Hz, 4H); 6.53(d, J=4.7 Hz, 2H), 5.08 (d, J=4.7 Hz, 2H).

3,7-Bis-(4-bromo-phenyl)-5,7-dihydro-1H,3H-pyrrolo[2,3-f]indole-2,6-dione(1.2)

2-(4-Bromo-phenyl)-N-{4-[2-(4-bromo-phenyl)-2-hydroxy-acetylamino]-phenyl}-2-hydroxy-acetamide(18.00 g, 33.70 mmol) (1.1) is added to concentrated sulfuric acid (180cm³) at 21° C. in a 500 cm³ round-bottom flask. After 18 hours stirring,the reaction mixture is poured onto ice and filtered off. The recoveredprecipitate is washed with water and dried for 18 hours at 80° C. in avacuum oven. The crude product is used without further purification(13.88 g, Yield: 83%).

3,7-Bis-(4-bromo-phenyl)-1H,5H-pyrrolo[2,3-f]indole-2,6-dione (1.3)

3,7-Bis-(4-bromo-phenyl)-5,7-dihydro-1H,3H-pyrrolo[2,3-f]indole-2,6-dione(7.250 g, 14.55 mmol) (1.2) was dissolved into acetic acid (215 cm³),chloranil (7.157 g, 29.11 mmol) is added and the reaction mixture heatedto 50° C. for 16 hours. After cooling down, the resulting precipitate isfiltered and washed with acetic acid. The recovered solid is purified bytrituration with nitrobenzene (120 cm³) at 200° C. followed bytrituration with diethyl ether (100 cm³) to obtain the pure product(4.512 g, Yield: 63%). NMR (1H, 300 MHz, DMSO): δ 10.37 (br, 2H), 7.71(d, J=8.7 Hz, 4H), 7.61 (d, J=8.7 Hz, 4H), 6.34 (s, 2H).

3,7-Bis-(4-bromo-phenyl)-1,5-dioctyl-1H,5H-pyrrolo[2,3-f]indole-2,6-dione(1.4)

3,7-Bis-(4-bromo-phenyl)-1H,5H-pyrrolo[2,3-f]indole-2,6-dione (1.250 g,2.519 mmol) (1.3) is dissolved into anhydrous dimethylformamide (50 cm³)and then potassium carbonate (3.482 g, 25.19 mmol) and 1-bromo-octane(1.1 cm³, 6.3 mmol) is added. The resulting mixture is heated to 90° C.for 21 hours before being cooled down, poured into methanol (500 cm³)and filtered to recover the pure product (1.320 g, Yield: 73%). NMR (1H,300 MHz, CDCl₃): δ 7.64 (d, J=8.7 Hz, 4H); 7.57 (d, J=8.7 Hz, 4H); 6.26(s, 2H); 3.62 (t, J=7.1 Hz, 4H); 1.63 (m, 4H); 1.32 (m, 8H); 1.26 (m,12H); 0.87 (t, J=6.8 Hz, 6H).

Poly(2,6-[4,8-dioctyl-benzo{1,2-b;4,5-b}dithiophene]-alt-[3,7-bis-{phenyl-4-ene}-1,5-dioctyl-1H,5H-pyrrolo{2,3-f}indole-2,6-dione)(1.5)

In a microwave tube,3,7-bis-(4-bromo-phenyl)-1,5-dioctyl-1H,5H-pyrrolo[2,3-f]indole-2,6-dione(1.4) (360.3 mg, 0.5000 mmol),4,8-dioctyl-2,6-bis-trimethylstannanyl-benzo[1,2-b;4,5-b]dithiophene(370.2 mg, 0.5000 mmol), tris(dibenzylideneacetone)dipalladium(0) (4.6mg, 0.0050 mmol) and tri(o-tolyl)phosphine (6.1 mg, 0.020 mmol) aredissolved in degassed toluene (8.0 cm³) and degassed dimethylformamide(2.0 cm³). The reaction mixture is further degassed and the reactionmixture heated over microware (Initiator, Biotage AB) at 120° C. for 2minutes, 140° C. for 2 minutes, 160° C. for 10 minutes and 180° C. for 5minutes. The polymer is purified by precipitation into methanol:water(10:1), filtered and washed sequentially via Soxhlet extraction withacetone, petroleum ether (40-60° C.), chloroform and chlorobenzene. Thechlorobenzene fraction is reduced to a smaller volume in vacuo andprecipitated into methanol (200 cm³). The precipitated polymer isfiltered and dried under vacuum at 25° C. overnight to afford theproduct (35 mg, yield 7%). GPC (1,2,4-trichlorobenzene, 140° C.):M_(n)=5.6 kg·mol⁻¹, M_(w)=7.7 kg·mol⁻¹.

Example 23,7-Bis-(4-bromo-phenyl)-1,5-bis-(2-hexyl-decyl)-1H,5H-pyrrolo[2,3-f]indole-2,6-dione(2.1)

3,7-Bis-(4-bromo-phenyl)-1H,5H-pyrrolo[2,3-f]indole-2,6-dione (1.500 g,3.023 mmol) (1.3) is dissolved into anhydrous dimethylformamide (60 cm³)and then potassium carbonate (4.178 g, 30.23 mmol) and7-bromomethyl-pentadecane (2.308 g, 7.558 mmol) are added. The resultingmixture is heated to 90° C. for 21 hours before been cooling down,poured into methanol (400 cm³), filtered and washed with water (200 cm³)to recover the pure product (1.525 g, Yield: 53%). NMR (1H, 300 MHz,CDCl₃): δ 7.61 (d, J=8.7 Hz, 4H), 7.57 (d, J=8.6 Hz, 4H), 6.29 (s, 2H),3.50 (d, J=7.3 Hz, 4H), 1.76 (m, 2H), 1.28 (m, 48H), 0.86 (t, J=7.1 Hz,12H)

Poly(2,6-[4,8-didodecyl-benzo{1,2-b;4,5-b′}dithiophene]-alt-[3,7-bis-{phenyl-4-ene}-1,5-(2-hexyl-decyl)-1H,5H-pyrrolo{2,3-f}indole-2,6-dione)(2.2)

In a 25 cm³ round bottom flask,3,7-bis-(4-bromo-phenyl)-1,5-(2-hexyl-decyl)-1H,5H-pyrrolo[2,3-f]indole-2,6-dione(2.1) (472.5 mg, 0.5000 mmol),4,8-didodecyl-2,6-bis-trimethylstannanyl-benzo[1,2-b;4,5-b]dithiophene(426.3 mg, 0.5000 mmol), tris(dibenzylideneacetone)dipalladium(0) (4.6mg, 0.0050 mmol) and tri(o-tolyl)phosphine (6.1 mg, 0.020 mmol) aredissolved in degassed toluene (8.0 cm³) and degassedN,N-dimethylformamide (2.0 cm³). The reaction mixture is furtherdegassed and the reaction mixture heated at 110° C. for 120 minutes. Thepolymer is purified by precipitation into methanol, filtered and washedsequentially via Soxhlet extraction with acetone, petroleum ether(40-60° C.) and chloroform. The chloroform fraction is reduced to asmaller volume in vacuo and precipitated into methanol (200 cm³). Theprecipitated polymer is filtered and dried under vacuum at 25° C.overnight to afford the product (641 mg, yield 97%). GPC(1,2,4-trichlorobenzene, 140° C.): M_(n)=44.7 kg·mol⁻¹, M_(w)=128.5kg·mol⁻¹.

Example 33,7-Bis-(4-bromo-phenyl)-4,8-dioctyl-benzo[1,2-b;4,5-b′]difuran-2,6-dione(3.1)

In a 100 cm³ flask fitted with a condenser and a reverse Dean-Starkapparatus, (4-bromo-phenyl)-hydroxy-acetic acid (6.043 g, 26.16 mmol)and 2,5-dioctyl-benzene-1,4-diol (Bao, Z.; Chan, W. K.; Yu, L. J. Am.Chem. Soc. 1995, 117, 12426-12435.) (3.500 g, 10.46 mmol) are dissolvedin 1,2-dichlorochlorobenzene (35 cm³). The reaction mixture is heated to200° C. and the generated water is distilled off the using a reverseDean-Stark apparatus. After 2 hours stirring, the reaction mixture iscooled down and the solvent was removed in vacuo. (9.501 g, Crude yield:125%). The crude3,7-bis-(4-bromo-phenyl)-4,8-dioctyl-3,7-dihydro-benzo[1,2-b;4,5-b′]difuran-2,6-dione(7.500 g, 10.35 mmol) is dissolved into acetic acid (125 cm³) at 50° C.before adding chloranil (5.090 g, 20.70 mmol). After 16 hours stirring,the reaction mixture is cooled down and the resulting precipitate isfiltered. The recovered solid is purified by column chromatography(95:5, petroleum ether (40-60):Ethyl acetate as eluant) to obtain acrystalline orange solid (0.642 g, Yield: 9%). NMR (1H, 300 MHz, CDCl₃):δ 7.63 (d, J=8.5 Hz, 4H); 7.30 (d, J=8.5 Hz, 4H); 2.46 (m, 4H); 1.19 (m,16H); 0.98 (m, 8H); 0.88 (t, J=7.1 Hz, 6H)

Poly(2,6-[4,8-didodecyl-benzo{1,2-b;4,5-b′}dithiophene]-alt-[3,7-bis-{phenyl-4-ene}-4,8-dioctyl-benzo[1,2-b;4,5-b′]difuran-2,6-dione)(3.2)

In a 25 cm³ round bottom flask,3,7-bis-(4-bromo-phenyl)-4,8-dioctyl-benzo[1,2-b;4,5-b′]difuran-2,6-dione(3.1) (361.3 mg, 0.5000 mmol),4,8-didodecyl-2,6-bis-trimethylstannanyl-benzo[1,2-b;4,5-b]dithiophene(426.3 mg, 0.5000 mmol), tris(dibenzylideneacetone)dipalladium(0) (4.6mg, 0.0050 mmol) and tri(o-tolyl)phosphine (6.1 mg, 0.020 mmol) aredissolved in degassed toluene (12.0 cm³) and degassedN,N-dimethylformamide (3.0 cm³). The reaction mixture is furtherdegassed and heated to 110° C. for 120 minutes. The polymer is purifiedby precipitation into methanol, filtered and dried under vacuum at 25°C. overnight to afford the product (452 mg, yield 83%). GPC(chlorobenzene, 50° C.): M_(n)=1.1 kg·mol⁻¹, M_(w)=1.4 kg·mol⁻¹.

Example 4 7-(2,2-Dibromo-vinyl)-pentadecane (4.1)

Carbon tetrabromide (218 g, 657 mmol) is dissolved in anhydrousdichloromethane (1600 cm³) and cooled to 0° C. Triphenylphosphine (345g, 1.32 mol) is added in one portion, the mixture exothermed to 15° C.and is re-cooled to 0° C., whilst stirring for 45 minutes.2-Hexyldecan-1-al (Price, S. C.; Stuart, A. C.; You, W.; Macromolecules2010, 43, 797-804) (79.0 g, 329 mmol) is added dropwise over 45 minutesand the mixture is allowed to warm to 23° C. After 2 hours, the reactionmixture is carefully poured into water (2000 cm³), the organic phase isseparated, dried over sodium sulfate, filtered and concentrated invacuo. The crude product is dissolved in dichloromethame (2000 cm³) andpassed twice through a plug of silica eluting with petroleum ether(40-60° C.) to yield the title product as a pale yellow oil (117.4 g,Yield: 90%). NMR (1H, 400 MHz, CDCl₃): δ 6.15 (d, J=9.6 Hz, 1H); 2.38(m, 1H); 1.29 (m, 24H); 0.91 (m, 6H).

7-Ethynyl-pentadecane (4.2)

n-BuLi (2.5 M in hexanes, 261 cm³, 652 mmol) is added dropwise over 60minutes to a solution of 7-(2,2-dibromo-vinyl)-pentadecane (4.1) (117 g,296 mmol) in anhydrous tetrahydrofuran (1350 cm³) at −78° C. The mixtureis stirred for 45 minutes at −78° C. and water (1.3 L) is carefullyadded. The reaction mixture exotherms to −10° C. and is allowed to warmto 23° C. whilst stirring over 18 hours. The organic phase is separated,washed with brine (1500 cm³), dried over sodium sulfate, filtered andconcentrated in vacuo. The crude oil is passed through a plug of silicaeluting with petroleum ether (40-60° C.). The pale yellow oil is furtherpurified by distillation under vacuum (96° C. at 0.85 mmHg) to give thetitle product as a colourless oil (57.7 g, Yield: 82%). NMR (1H, 300MHz, CDCl₃): δ 2.30 (m, 1H); 2.03 (d, J=2.4 Hz, 1H); 1.44 (m, 8H); 1.27(m, 16H); 0.88 (m, 6H).

1,4-Bis-(3-hexyl-undec-1-ynyl)-2,5-dimethoxy-benzene (4.3)

1,4-Diiodo-2,5-dimethoxy-benzene (3.750 g; 9.616 mmol),7-ethynyl-pentadecane (4.2) (5.116 g; 21.637 mmol), PdCl₂(PPh₃)₂ (0.169g; 240 μmol) and copper iodide (0.092 g; 481 μmol) are dissolved intotetrahydrofuran (50 cm³) and triethylamine (50 cm³). The resultingmixture is degassed for 30 minutes and then stirred at 60° C. for 17hours. The solvent is removed in vacuo and the crude product purified bycolumn chromatography (gradient from 100:00 to 75:25, Petroleum ether(40-60° C.) and dichlorobenzene) to afford a light yellow oil whichcrystallises upon standing (4.90 g, Yield: 84%). NMR (1H, 300 MHz,CDCl₃): δ 6.83 (s, 2H); 3.81 (s, 6H); 2.59 (m, 2H); 1.53 (m, 16H); 1.31(m, 32H); (m, 12H).

1,4-Bis-(3-hexyl-undecyl)-2,5-dimethoxy-benzene (4.4)

1,4-Bis-(3-hexyl-undec-1-ynyl)-2,5-dimethoxy-benzene (4.3) (7.70 g, 12.1mmol) is dissolved in tetrahydrofuran (200 cm³) under an atmosphere ofArgon. 10% Pd/C (1.25 g) is added, the mixture warmed to 30° C. (oilbath temperature) and stirred under an atmosphere of hydrogen for 2.5hours. The reaction mixture is filtered through a plug of celite and theplug washed through with ethyl acetate (2×50 cm³), and the filtrate isconcentrated in vacuo. The crude oil is purified by columnchromatography eluting with 2 to 5% ethyl acetate in petroleum ether(40-60° C.). A second purification by column chromatography is carriedout, eluting with 3% ethyl acetate in petroleum ether (40-60° C.) togive the title product as a colourless oil (7.00 g, 90%). NMR (1H, 400MHz, CDCl₃): δ 6.65 (s, 2H); 3.78 (s, 6H); 2.53 (m, 4H); 1.51 (m, 4H);1.28 (m, 50H); 0.89 (m, 12H)

2,5-Bis-(3-hexyl-undecyl)-benzene-1,4-diol (4.5)

1,4-Bis-(3-hexyl-undecyl)-2,5-dimethoxy-benzene (7.000 g; 11.38 mmol) isdissolved in anhydrous dichloromethane (115 cm³) before cooling down thesolution to −78° C. Neat boron tribromide (2.69 ml; 28.5 mmol) is addeddropwise over 15 minutes. The resulting mixture is stirred at −78° C.for 1 hour before being warmed to 23° C. for 18 hours. Methanol (25 cm³)and then diluted HCl (75 cm³) is added before pouring the reactionmixture into water. The organic layer is separated and the aqueous layerextracted tow times with diethyl ether (2×250 cm³). The organicfractions are combined, dried over magnesium sulfate and the solventsremoved under vacuum. The crude product is used, as it, without furtherpurification (6.51 g, Yield: 97%). NMR (1H, 300 MHz, CDCl₃): δ 6.54 (s,2H); 4.24 (br, 2H); 2.47 (m, 4H); 1.51 (m, 4H); 1.26 (m; 50H); 0.88 (t,J=6.7 Hz, 12H).

3,7-Bis-(4-bromo-phenyl)-4,8-bis-(3-hexyl-undecyl)-benzo[1,2-b;4,5-b′]difuran-2,6-dione(4.6)

2,5-Bis-(3-hexyl-undecyl)-benzene-1,4-diol (2.05 g; 3.49 mmol),(4-Bromo-phenyl)-hydroxy-acetic acid (2.02 g; 8.73 mmol) and1,2-dichlorobenzene (25.000 cm³) were stirred at 200° C. After 18 hours,2 cm³ of nitrobenzene is added and compressed air is bubbled into thereaction mixture to complete the oxidation process over three days. Thesolvent is removed in vacuo and the crude product purified several timesusing column chromatography (gradient from 75:25 to 50:50, petroleumether (40-60° C.) and dichloromethane). The product is finallytriturated with methanol to afford to title product as the orange-yellowproduct (131 mg, Yield: 4%). NMR (1H, 300 MHz, CDCl₃): δ 7.62 (d, J=8.5Hz, 4H); 7.31 (d, J=8.5 Hz, 4H); 2.49 (m, 4H); 1.26 (m, 54H); 0.89 (t,J=6.9 Hz, 12H).

Poly(2,6-[4,8-didodecyl-benzo{1,2-b;4,5-b′}dithiophene]-alt-[3,7-bis-{phenyl-4-ene}-4,8-(3-hexyl-undecyl)-benzo[1,2-b;4,5-b′]difuran-2,6-dione)(4.7)

In a microwave tube,3,7-bis-(4-bromo-phenyl)-4,8-bis-(3-hexyl-undecyl)-benzo[1,2-b;4,5-b′]difuran-2,6-dione(4.6) (110.3 mg, 0.1131 mmol),4,8-didodecyl-2,6-bis-trimethylstannanyl-benzo[1,2-b;4,5-b]dithiophene(96.4 mg, 0.113 mmol), tris(dibenzylideneacetone)dipalladium(0) (1.0 mg,0.0011 mmol) and tri(o-tolyl)phosphine (2.8 mg, 0.0091 mmol) aredissolved in degassed toluene (2.4 cm³) and degassedN,N-dimethylformamide (0.6 cm³). The reaction mixture is furtherdegassed and heated over microware (Initiator, Biotage AB) at 180° C.for 60 minutes. The polymer is purified by precipitation into methanol,filtered and washed sequentially via Soxhlet extraction with acetone andpetroleum ether (40-60° C.). The petroleum ether (40-60° C.) fraction isreduced to a smaller volume in vacuo and precipitated into isopropanol(100 cm³). The precipitated polymer is filtered and dried under vacuumat 25° C. overnight to afford the product (100 mg, Yield: 66%). GPC(chlorobenzene, 50° C.): M_(n)=10.6 kg·mol⁻¹, M_(w)=17.7 kg·mol⁻¹.

The invention claimed is:
 1. A polymer comprising in said polymeridentical or different repeating units of formula I

wherein the asterisks indicate a link to neighboring groups, and thepolymer is a conjugated polymer, X is O, S or NR^(x), R is, on eachoccurrence identically or differently, H, F, Cl, Br, I, CN, orstraight-chain, branched or cyclic alkyl with 1 to 35 C atoms, in whichone or more non-adjacent C atoms are optionally replaced by —O—, —S—,—CO—, —CO—O—, —O—CO—, —O—CO—O—, —CR⁰═CR⁰⁰— or —C≡C— and in which one ormore H atoms are optionally replaced by F, Cl, Br, I or CN, or denotearyl, heteroaryl, aryloxy, heteroaryloxy, arylcarbonyl,heteroarylcarbonyl, arylcarbonyloxy, heteroarylcarbonyloxy,aryloxycarbonyl or heteroaryloxycarbonyl having 4 to 30 ring atoms thatis unsubstituted or substituted by one or more non-aromatic groups R¹,R^(x) is on each occurrence identically or differently straight-chain,branched or cyclic alkyl with 1 to 30 C atoms, in which one or morenon-adjacent C atoms are optionally replaced by —O—, —S—, —CO—, —CO—O—,—O—CO—, O—CO—O—, —CR⁰═CR⁰⁰— or —C≡C— and in which one or more H atomsare optionally replaced by F, Cl, Br, I or CN, R⁰ and R⁰⁰ areindependently of each other H or optionally substituted carbyl orhydrocarbyl optionally comprising one or more hetero atoms, R¹ is oneach occurrence identically or differently H, halogen, —CN, —NC, —NCO,—NCS, —OCN, —SCN, —C(═O)NR⁰R⁰⁰, —C(═O)X⁰, —C(═O)R⁰, —NH₂, —NR⁰R⁰⁰, —SH,—SR⁰, —SO₃H, —SO₂R⁰, —OH, —NO₂, —CF₃, —SF₅, optionally substitutedsilyl, carbyl or hydrocarbyl with 1 to 40 C atoms that is optionallysubstituted and optionally comprises one or more hetero atoms, or P-Sp-,P is a polymerizable or crosslinkable group, Sp is a spacer group or asingle bond, X⁰ is halogen.
 2. The polymer comprising repeating unitswhich contain a unit of formula I as defined in claim 1 and/or containone or more aryl or heteroaryl units that are optionally substituted,wherein at least one of the repeating units in the polymer contains atleast one unit of formula I as defined in claim
 1. 3. The polymeraccording to claim 1, of formula II—[(Ar¹—U—Ar²)_(x)—(Ar³)_(y)]_(n)—  II wherein U is on each occurrenceidentically or differently a unit of formula I as defined in claim 1,Ar¹, Ar², Ar^(a) are, on each occurrence identically or differently, andindependently of each other, optionally substituted aryl or heteroaryl,Y¹ and Y² are independently of each other H, F, Cl or CN, x is on eachoccurrence identically or differently 0, 1 or 2, wherein in at least onerepeating unit, i.e. in at least one unit —[(Ar¹—U—Ar²)_(x)—(Ar³)_(y)]—,x is 1, y is on each occurrence identically or differently 0, 1 or 2, nis an integer>1.
 4. The polymer according to claim 3, of formula IIaR²—[(Ar¹—U—Ar²)_(x)—(Ar³)_(y)]_(n)—R³  IIa wherein U, Ar¹⁻³, n, x and yhave the meanings of claim 3, and R² and R³ have independently of eachother one of the meanings of R¹, or denote H, —CH₂Cl, —CHO, —CH═CH₂,—SiR′R″R′″, —SnR′R″R′″, —BR′R″, —B(OR′)(OR″), —B(OH)₂, or P-Sp, whereinP and Sp are as defined above, and R′, R″ and R′″ have independently ofeach other one of the meanings of R⁰, and two of R′, R″ and R′″ may alsoform a ring together with the hetero atom to which they are attached. 5.The polymer according to claim 2, wherein the aryl or heteroaryl unitsare independently of each other 1,4-phenylene, thiophene-2,5-diyl,thiazole-2,5-diyl, selenophene-2,5-diyl, furan-2,5-diyl,thieno[3,2-b]thiophene-2,5-diyl, thieno[2,3-b]thiophene-2,5-diyl,selenopheno[3,2-b]selenophene-2,5-diyl,selenopheno[2,3-b]selenophene-2,5-diyl,selenopheno[3,2-b]thiophene-2,5-diyl, orselenopheno[2,3-b]thiophene-2,5-diyl, all of which are unsubstituted, ormono- or polysubstituted with R or R¹ as defined in claim
 2. 6. Thepolymer according to claim 2, wherein the aryl or heteroaryl units areon each occurrence identically or differently 1,4-phenylene,thiophene-2,5-diyl, selenophene-2,5-diyl,thieno[3,2-b]thiophene-2,5-diyl, thieno[2,3-b]thiophene-2,5-diyl,selenopheno[3,2-b]selenophene-2,5-diyl,selenopheno[2,3-b]selenophene-2,5-diyl,selenopheno[3,2-b]thiophene-2,5-diyl,selenopheno[2,3-b]thiophene-2,5-diyl,benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl, 2,2-dithiophene,2,2-diselenophene, dithieno[3,2-b:2′,3′-d]silole-5,5-diyl,4H-cyclopenta[2,1-b:3,4-b′]dithiophene-2,6-diyl, carbazole-2,7-diyl,fluorene-2,7-diyl, indaceno[1,2-b:5,6-N]dithiophene-2,7-diyl,benzo[1″,2″:4,5;4″,5″:4′,5′]bis(silolo[3,2-b:3′,2′-b′]thiophene)-2,7-diyl,phenanthro[1,10,9,8-c,d,e,f,g]carbazole-2,7-diyl,benzo[2,1,3]thiadiazole-4,7-diyl, benzo[2,1,3]selenadiazole-4,7-diyl,benzo[2,1,3]oxadiazole-4,7-diyl, 2H-benzotriazole-4,7-diyl,3,4-difluorothiophene-2,5-diyl, thieno[3,4-b]pyrazine-2,5-diyl,quinoxaline-5,8-diyl, thieno[3,4-b]thiophene-4,6-diyl,thieno[3,4-b]thiophene-6,4-diyl,3,6-di-thien-2-yl-pyrrolo[3,4-c]pyrrole-1,4-dione, or[1,3]thiazolo[5,4-d][1,3]thiazole-2,5-diyl, all of which areunsubstituted, or mono- or polysubstituted with R or R¹ as defined inclaim
 2. 7. The polymer according to claim 6, wherein R is primary alkylor alkoxy with 1 to 30 C atoms, secondary alkyl or alkoxy with 3 to 30 Catoms, or tertiary alkyl or alkoxy with 4 to 30 C atoms, wherein in allthese groups one or more H atoms are optionally replaced by F, or R isaryl, aryloxy, heteroaryl or heteroaryloxy that is optionally alkylatedor alkoxylated and has 4 to 30 ring atoms.
 8. A mixture or blendcomprising one or more polymers according to claim 1 and one or morecompounds or polymers having semiconducting, charge transport,hole/electron transport, hole/electron blocking, electricallyconducting, photoconducting or light emitting properties.
 9. Aformulation comprising one or more polymers, according to claim 1, andone or more solvents.
 10. A charge transport, semiconducting,electrically conducting, photoconducting or light emitting material inoptical, electrooptical, electronic, electroluminescent orphotoluminescent components or devices which comprises a polymeraccording to claim
 1. 11. An optical, electrooptical or electroniccomponent or device comprising one or more polymers, according toclaim
 1. 12. A component or device according to claim 11, which is anorganic field effect transistor (OFET), a thin film transistor (TFT), anintegrated circuit (IC), a logic circuit, a capacitor, a radio frequencyidentification (RFID) tag, an organic light emitting diode (OLED), anorganic light emitting transistor (OLET), a flat panel display, abacklight of display, an organic photovoltaic device (OPV), a solarcell, a laser diode, a photoconductor, a photodetector, anelectrophotographic device, an electrophotographic recording device, anorganic memory device, a sensor device, a charge injection layer, acharge transport layer or an interlayer in a polymer light emittingdiode (PLEDs), a Schottky diode, a planarizing layer, an antistaticfilm, a polymer electrolyte membrane (PEM), a conducting substrate, aconducting pattern, an electrode material in a battery, an alignmentlayer, a biosensor, a biochip, a security marking, a security device, ora component or device for detecting and discriminating DNA sequences.13. The component or device according to claim 11, which is an OFET or abulk heterojunction OPV device.
 14. A monomer of formula IaR²—U—R³  Ia wherein U is a unit of formula I

wherein the asterisks indicate a link to neighboring groups, X is O, Sor NR^(x), R is, on each occurrence identically or differently, H, F,Cl, Br, I, CN, or straight-chain, branched or cyclic alkyl with 1 to 35C atoms, in which one or more non-adjacent C atoms are optionallyreplaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —CR⁰═CR⁰⁰— or—C≡C— and in which one or more H atoms are optionally replaced by F, Cl,Br, I or CN, or denote aryl, heteroaryl, aryloxy, heteroaryloxy,arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy,heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl having 4to 30 ring atoms that is unsubstituted or substituted by one or morenon-aromatic groups R¹, R^(x) is on each occurrence identically ordifferently straight-chain, branched or cyclic alkyl with 1 to 30 Catoms, in which one or more non-adjacent C atoms are optionally replacedby —O—, —S—, —CO—, —CO—O—, —O—CO—, O—CO—O—, —CR⁰═CR⁰⁰— or —C≡C— and inwhich one or more H atoms are optionally replaced by F, Cl, Br, I or CN,R⁰ and R⁰⁰ are independently of each other H or optionally substitutedcarbyl or hydrocarbyl optionally comprising one or more hetero atoms, R¹is on each occurrence identically or differently H, halogen, —CN, —NC,—NCO, —NCS, —OCN, —SCN, —C(═O)NR⁰R⁰⁰, —C(═O)X⁰, —C(═O)R⁰, —NH₂, —NR⁰R⁰⁰,—SH, —SR⁰, —SO₃H, —SO₂R⁰, —OH, —NO₂, —CF₃, —SF₅, optionally substitutedsilyl, carbyl or hydrocarbyl with 1 to 40 C atoms that is optionallysubstituted and optionally comprises one or more hetero atoms, or P-Sp-,P is a polymerizable or crosslinkable group, Sp is a spacer group or asingle bond, X⁰ is halogen, and R² and R³ are, independently of eachother, Cl, Br, I, O-tosylate, O-triflate, O-mesylate, O-nonaflate,—SiMe₂F, —SiMeF₂, —O—SO₂Z¹, —B(OZ²)₂, —CZ³═C(Z³)₂, —C≡CH or —Sn(Z⁴)₃,wherein Z¹⁻⁴ are alkyl or aryl, each being optionally substituted, andtwo groups Z² may also form a cyclic group.
 15. A process of preparing apolymer according to claim 1, by coupling: one or more monomers offormula IaR²—U—R³  Ia wherein U is a unit of formula I

wherein the asterisks indicate a link to neighboring groups, X is O, Sor NR^(x), R is, on each occurrence identically or differently, H, F,Cl, Br, I, CN, or straight-chain, branched or cyclic alkyl with 1 to 35C atoms, in which one or more non-adjacent C atoms are optionallyreplaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —CR⁰═CR⁰⁰— or—C≡C— and in which one or more H atoms are optionally replaced by F, Cl,Br, I or CN, or denote aryl, heteroaryl, aryloxy, heteroaryloxy,arylcarbonyl, heteroarylcarbonyl, arylcarbonyloxy,heteroarylcarbonyloxy, aryloxycarbonyl or heteroaryloxycarbonyl having 4to 30 ring atoms that is unsubstituted or substituted by one or morenon-aromatic groups R¹, R^(x) is on each occurrence identically ordifferently straight-chain, branched or cyclic alkyl with 1 to 30 Catoms, in which one or more non-adjacent C atoms are optionally replacedby —O—, —S—, —CO—, —CO—O—, —O—CO—, O—CO—O—, —CR⁰═CR⁰⁰— or —C≡C— and inwhich one or more H atoms are optionally replaced by F, Cl, Br, I or CN,R⁰ and R⁰⁰ are independently of each other H or optionally substitutedcarbyl or hydrocarbyl optionally comprising one or more hetero atoms, R¹is on each occurrence identically or differently H, halogen, —CN, —NC,—NCO, —NCS, —OCN, —SCN, —C(═O)NR⁰R⁰⁰, —C(═O)X⁰, —C(═O)R⁰, —NH₂, —NR⁰R⁰⁰,—SH, —SR⁰, —SO₃H, —SO₂R⁰, —OH, —NO₂, —CF₃, —SF₅, optionally substitutedsilyl, carbyl or hydrocarbyl with 1 to 40 C atoms that is optionallysubstituted and optionally comprises one or more hetero atoms, or P-Sp-,P is a polymerizable or crosslinkable group, Sp is a spacer group or asingle bond, X⁰ is halogen, and R² and R³ are, independently of eachother, Cl, Br, I, O-tosylate, O-triflate, O-mesylate, O-nonaflate,—SiMe₂F, —SiMeF₂, —O—SO₂Z¹, —B(OZ²)₂, —CZ³═C(Z³)₂, —C≡CH or —Sn(Z⁴)₃,wherein Z¹⁻⁴ are alkyl or aryl, each being optionally substituted, andtwo groups Z² may also form a cyclic group, and/or one or more monomersof the formulaR²—Ar³—R³ wherein R² and R³ are as defined above and Ar³ is, on eachoccurrence identically or differently, optionally substituted aryl orheteroaryl, in an aryl-aryl coupling reaction.
 16. The formulationaccording to claim 9, wherein the solvent is an organic solvent.